Getting the screen resolution using PHP

This is a very simple process. Yes, you cannot get the width and height in PHP. It is true that JQuery can provide the screen's width and height. First go to https://github.com/carhartl/jquery-cookie and get jquery.cookie.js. Here is example using php to get the screen width and height:

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Test</title>
        <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
        <script src="https://ajax.googleapis.com/ajax/libs/jqueryui/1.12.1/jquery-ui.min.js"></script>
        <script src="js/jquery.cookie.js"></script>
        <script type=text/javascript>
            function setScreenHWCookie() {
                $.cookie('sw',screen.width);
                $.cookie('sh',screen.height);
                return true;
            }
            setScreenHWCookie();
        </script>
    </head>
    <body>
        <h1>Using jquery.cookie.js to store screen height and width</h1>
    <?php
         if(isset($_COOKIE['sw'])) { echo "Screen width: ".$_COOKIE['sw']."<br/>";}
         if(isset($_COOKIE['sh'])) { echo "Screen height: ".$_COOKIE['sh']."<br/>";}
    ?>
    </body>
    </html>

I have a test that you can execute: http://rw-wrd.net/test.php

detect key press in python?

I would suggest you use PyGame and add an event handle.

http://www.pygame.org/docs/ref/event.html

Loop over html table and get checked checkboxes (JQuery)

use .filter(':has(:checkbox:checked)' ie:

$('#mytable tr').filter(':has(:checkbox:checked)').each(function() {
 $('#out').append(this.id);
});

How to apply style classes to td classes?

A more definite way to target a td is table tr td { }

How can I make a Python script standalone executable to run without ANY dependency?

Not exactly a packaging of the Python code, but there is now also Grumpy from Google, which transpiles the code to Go.

It doesn't support the Python C API, so it may not work for all projects.

Export multiple classes in ES6 modules

// export in index.js
export { default as Foo } from './Foo';
export { default as Bar } from './Bar';

// then import both
import { Foo, Bar } from 'my/module';

How to drop all tables from the database with manage.py CLI in Django?

This answer is for postgresql DB:

Run: echo 'drop owned by some_user' | ./manage.py dbshell

NOTE: some_user is the name of the user you use to access the database, see settings.py file:

default_database = {
    'ENGINE': 'django.db.backends.postgresql_psycopg2',
    'NAME': 'somedbname',
    'USER': 'some_user',
    'PASSWORD': 'somepass',
    'HOST': 'postgresql',
    'PORT': '',
}

How to check that a JCheckBox is checked?

Use the isSelected method.

You can also use an ItemListener so you'll be notified when it's checked or unchecked.

Explain why constructor inject is better than other options

To make it simple, let us say that we can use constructor based dependency injection for mandatory dependencies and setter based injection for optional dependencies. It is a rule of thumb!!

Let's say for example.

If you want to instantiate a class you always do it with its constructor. So if you are using constructor based injection, the only way to instantiate the class is through that constructor. If you pass the dependency through constructor it becomes evident that it is a mandatory dependency.

On the other hand, if you have a setter method in a POJO class, you may or may not set value for your class variable using that setter method. It is completely based on your need. i.e. it is optional. So if you pass the dependency through setter method of a class it implicitly means that it is an optional dependency. Hope this is clear!!

What is the correct way to restore a deleted file from SVN?

The easiest way I have been able to restore files and not lose revision history is using SVN copy, the merge example above to me seems like a more complex way to achieve the same thing. Why is there a need to merge when you simply want to restore a revision?

I use the following in this instance and it works quite well.

svn copy -m 'restoring file' -r <rev_number_file_to_restore> http://from/file.cs http://pathTo/file.cs

I always seem to use svn copy as a server operation so not sure if it works with two working paths.

Return index of greatest value in an array

If you create a copy of the array and sort it descending, the first element of the copy will be the largest. Than you can find its index in the original array.

var sorted = [...arr].sort((a,b) => b - a)
arr.indexOf(sorted[0])

Time complexity is O(n) for the copy, O(n*log(n)) for sorting and O(n) for the indexOf.

If you need to do it faster, Ry's answer is O(n).

Trim a string in C

void inPlaceStrTrim(char* str) {
    int k = 0;
    int i = 0;
    for (i=0; str[i] != '\0';) {
        if (isspace(str[i])) {
            // we have got a space...
            k = i;
            for (int j=i; j<strlen(str)-1; j++) {
                str[j] = str[j+1];
            }
            str[strlen(str)-1] = '\0';
            i = k; // start the loop again where we ended..
        } else {
            i++;
        }
    }
}

Simple way to query connected USB devices info in Python?

If you just need the name of the device here is a little hack which i wrote in bash. To run it in python you need the following snippet. Just replace $1 and $2 with Bus number and Device number eg 001 or 002.

import os
os.system("lsusb | grep \"Bus $1 Device $2\" | sed 's/\// /' | awk '{for(i=7;i<=NF;++i)print $i}'")

Alternately you can save it as a bash script and run it from there too. Just save it as a bash script like foo.sh make it executable.

#!/bin/bash
myvar=$(lsusb | grep "Bus $1 Device $2" | sed 's/\// /' | awk '{for(i=7;i<=NF;++i)print $i}')
echo $myvar

Then call it in python script as

import os
os.system('foo.sh')

How to enable scrolling on website that disabled scrolling?

What worked for me was disabling the position: fixed; CSS.

Generating unique random numbers (integers) between 0 and 'x'

I think, this is the most human approach (with using break from while loop), I explained it's mechanism in comments.

function generateRandomUniqueNumbersArray (limit) {

    //we need to store these numbers somewhere
    const array = new Array();
    //how many times we added a valid number (for if statement later)
    let counter = 0;

    //we will be generating random numbers until we are satisfied
    while (true) {

        //create that number
        const newRandomNumber = Math.floor(Math.random() * limit);

        //if we do not have this number in our array, we will add it
        if (!array.includes(newRandomNumber)) {
            array.push(newRandomNumber);
            counter++;
        }

        //if we have enought of numbers, we do not need to generate them anymore
        if (counter >= limit) {
            break;
        }
    }

    //now hand over this stuff
    return array;
}

You can of course add different limit (your amount) to the last 'if' statement, if you need less numbers, but be sure, that it is less or equal to the limit of numbers itself - otherwise it will be infinite loop.

Loading DLLs at runtime in C#

Activator.CreateInstance() returns an object, which doesn't have an Output method.

It looks like you come from dynamic programming languages? C# is definetly not that, and what you are trying to do will be difficult.

Since you are loading a specific dll from a specific location, maybe you just want to add it as a reference to your console application?

If you absolutely want to load the assembly via Assembly.Load, you will have to go via reflection to call any members on c

Something like type.GetMethod("Output").Invoke(c, null); should do it.

include antiforgerytoken in ajax post ASP.NET MVC

The token won't work if it was supplied by a different controller. E.g. it won't work if the view was returned by the Accounts controller, but you POST to the Clients controller.

sys.argv[1] meaning in script

sys.argv is a list containing the script path and command line arguments; i.e. sys.argv[0] is the path of the script you're running and all following members are arguments.

How do I make a composite key with SQL Server Management Studio?

enter image description here

Open the design table tab
Highlight your two INT fields (Ctrl/Shift+click on the grey blocks in the very first column)
Right click -> Set primary key

Error:Conflict with dependency 'com.google.code.findbugs:jsr305'

REACT NATIVE

If you looking for react native solution, then write this snippet in your affected node_modules gradle build file, e.g. firebase in my case.

android {
    configurations.all {
        resolutionStrategy.force 'com.google.code.findbugs:jsr305:3.0.0'
    }
}

Best way to create a temp table with same columns and type as a permanent table

select * into #temptable from tablename where 1<>1

Checking for #N/A in Excel cell from VBA code

First check for an error (N/A value) and then try the comparisation against cvErr(). You are comparing two different things, a value and an error. This may work, but not always. Simply casting the expression to an error may result in similar problems because it is not a real error only the value of an error which depends on the expression.

If IsError(ActiveWorkbook.Sheets("Publish").Range("G4").offset(offsetCount, 0).Value) Then
  If (ActiveWorkbook.Sheets("Publish").Range("G4").offset(offsetCount, 0).Value <> CVErr(xlErrNA)) Then
    'do something
  End If
End If

Sql server - log is full due to ACTIVE_TRANSACTION

Restarting the SQL Server will clear up the log space used by your database. If this however is not an option, you can try the following:

* Issue a CHECKPOINT command to free up log space in the log file.

* Check the available log space with DBCC SQLPERF('logspace'). If only a small 
  percentage of your log file is actually been used, you can try a DBCC SHRINKFILE 
  command. This can however possibly introduce corruption in your database. 

* If you have another drive with space available you can try to add a file there in 
  order to get enough space to attempt to resolve the issue.

Hope this will help you in finding your solution.

Microsoft.ReportViewer.Common Version=12.0.0.0

First install SQLSysClrTypes for Ms SQL 2014 and secondly install ReportViewer for ms sql 2014

Restart your application or project, in my case its resolved.

.ssh/config file for windows (git)

For me worked only adding the config or ssh_config file that was on the dir ~/.ssh/config on my Linux system on the c:\Program Files\Git\etc\ssh\ directory on Windows.

In some git versions we need to edit the C:\Users\<username>\AppData\Local\Programs\Git\etc\ssh\ssh_config file.

After that, I was able to use all the alias and settings that I normally used on my Linux connecting or pushing via SSH on the Git Bash.

TypeScript: casting HTMLElement

var script = (<HTMLScriptElement[]><any>document.getElementsByName(id))[0];

CodeIgniter - how to catch DB errors?

You must turn debug off for database in config/database.php ->

$db['default']['db_debug'] = FALSE;

It is better for your website security.

How to force cp to overwrite without confirmation

cp -u ...
cp --update ...

also works.

IllegalMonitorStateException on wait() call

Since you haven't posted code, we're kind of working in the dark. What are the details of the exception?

Are you calling Thread.wait() from within the thread, or outside it?

I ask this because according to the javadoc for IllegalMonitorStateException, it is:

Thrown to indicate that a thread has attempted to wait on an object's monitor or to notify other threads waiting on an object's monitor without owning the specified monitor.

To clarify this answer, this call to wait on a thread also throws IllegalMonitorStateException, despite being called from within a synchronized block:


     private static final class Lock { }
     private final Object lock = new Lock();

    @Test
    public void testRun() {
        ThreadWorker worker = new ThreadWorker();
        System.out.println ("Starting worker");
        worker.start();
        System.out.println ("Worker started - telling it to wait");
        try {
            synchronized (lock) {
                worker.wait();
            }
        } catch (InterruptedException e1) {
            String msg = "InterruptedException: [" + e1.getLocalizedMessage() + "]";
            System.out.println (msg);
            e1.printStackTrace();
            System.out.flush();
        }
        System.out.println ("Worker done waiting, we're now waiting for it by joining");
        try {
            worker.join();
        } catch (InterruptedException ex) { }

    }

How to exclude property from Json Serialization

If you are using System.Web.Script.Serialization in the .NET framework you can put a ScriptIgnore attribute on the members that shouldn't be serialized. See the example taken from here:

Consider the following (simplified) case:
public class User {
    public int Id { get; set; }
    public string Name { get; set; }
    [ScriptIgnore]
    public bool IsComplete
    {
        get { return Id > 0 && !string.IsNullOrEmpty(Name); }
    } 
} 
In this case, only the Id and the Name properties will be serialized, thus the resulting JSON object would look like this:
{ Id: 3, Name: 'Test User' }

PS. Don't forget to add a reference to "System.Web.Extensions" for this to work

How to make a vertical line in HTML

Put a <div> around the markup where you want the line to appear to next, and use CSS to style it:

_x000D_

.verticalLine {_x000D_
  border-left: thick solid #ff0000;_x000D_
}

_x000D_

<div class="verticalLine">_x000D_
  some other content_x000D_
</div>

_x000D_

how to check if a datareader is null or empty

AMG - Sorry all, was having a blond moment. The field "Additional" was added to the database after I had initially designed the database.

I updated all my code to use this new field, however I forgot to update the actual datareader code that was making the call to select the database fields, therefore it wasn't calling "Additional"

Search for value in DataGridView in a column

"MyTable".DefaultView.RowFilter = " LIKE '%" + textBox1.Text + "%'"; this.dataGridView1.DataSource = "MyTable".DefaultView;

How about the relation to the database connections and the Datatable? And how should i set the DefaultView correct?

I use this code to get the data out:

con = new System.Data.SqlServerCe.SqlCeConnection();
con.ConnectionString = "Data Source=C:\\Users\\mhadj\\Documents\\Visual Studio 2015\\Projects\\data_base_test_2\\Sample.sdf";
con.Open();

DataTable dt = new DataTable();

adapt = new System.Data.SqlServerCe.SqlCeDataAdapter("select * from tbl_Record", con);        
adapt.Fill(dt);        
dataGridView1.DataSource = dt;
con.Close();

Function passed as template argument

In your template

template <void (*T)(int &)>
void doOperation()

The parameter T is a non-type template parameter. This means that the behaviour of the template function changes with the value of the parameter (which must be fixed at compile time, which function pointer constants are).

If you want somthing that works with both function objects and function parameters you need a typed template. When you do this, though, you also need to provide an object instance (either function object instance or a function pointer) to the function at run time.

template <class T>
void doOperation(T t)
{
  int temp=0;
  t(temp);
  std::cout << "Result is " << temp << std::endl;
}

There are some minor performance considerations. This new version may be less efficient with function pointer arguments as the particular function pointer is only derefenced and called at run time whereas your function pointer template can be optimized (possibly the function call inlined) based on the particular function pointer used. Function objects can often be very efficiently expanded with the typed template, though as the particular operator() is completely determined by the type of the function object.

How to add "active" class to wp_nav_menu() current menu item (simple way)

In header.php insert this code to show menu:

<?php
    wp_nav_menu(
        array(
            'theme_location' => 'menu-one',
            'walker' => new Custom_Walker_Nav_Menu_Top
        )
    );
?>

In functions.php use this:

class Custom_Walker_Nav_Menu_top extends Walker_Nav_Menu
{
    function start_el( &$output, $item, $depth = 0, $args = array(), $id = 0 ) {
        $is_current_item = '';
        if(array_search('current-menu-item', $item->classes) != 0)
        {
            $is_current_item = ' class="active"';
        }
        echo '<li'.$is_current_item.'><a href="'.$item->url.'">'.$item->title;
    }

    function end_el( &$output, $item, $depth = 0, $args = array() ) {
        echo '</a></li>';
    }
}

How to escape hash character in URL

Percent encoding. Replace the hash with %23.

The Role Manager feature has not been enabled

If you are using ASP.NET Identity UserManager you can get it like this as well:

var userManager = Request.GetOwinContext().GetUserManager<ApplicationUserManager>();

var roles = userManager.GetRoles(User.Identity.GetUserId());

If you have changed key for user from Guid to Int for example use this code:

var roles = userManager.GetRoles(User.Identity.GetUserId<int>());

alternatives to REPLACE on a text or ntext datatype

IF your data won't overflow 4000 characters AND you're on SQL Server 2000 or compatibility level of 8 or SQL Server 2000:

UPDATE [CMS_DB_test].[dbo].[cms_HtmlText] 
SET Content = CAST(REPLACE(CAST(Content as NVarchar(4000)),'ABC','DEF') AS NText)
WHERE Content LIKE '%ABC%'

For SQL Server 2005+:

UPDATE [CMS_DB_test].[dbo].[cms_HtmlText] 
SET Content = CAST(REPLACE(CAST(Content as NVarchar(MAX)),'ABC','DEF') AS NText)
WHERE Content LIKE '%ABC%'

How to set an image's width and height without stretching it?

you can try setting the padding instead of the height/width.

How to solve 'Redirect has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header'?

In addition to what awd mentioned about getting the person responsible for the server to reconfigure (an impractical solution for local development) I use a change-origin chrome plugin like this:

Moesif Orign & CORS Changer

You can make your local dev server (ex: localhost:8080) to appear to be coming from 172.16.1.157:8002 or any other domain.

How do I convert the date from one format to another date object in another format without using any deprecated classes?

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

             String fromDateFormat = "dd/MM/yyyy";
             String fromdate = 15/03/2018; //Take any date

             String CheckFormat = "dd MMM yyyy";//take another format like dd/MMM/yyyy
             String dateStringFrom;

             Date DF = new Date();


              try
              {
                 //DateFormatdf = DateFormat.getDateInstance(DateFormat.SHORT);
                 DateFormat FromDF = new SimpleDateFormat(fromDateFormat);
                 FromDF.setLenient(false);  // this is important!
                 Date FromDate = FromDF.parse(fromdate);
                 dateStringFrom = new 
                 SimpleDateFormat(CheckFormat).format(FromDate);
                 DateFormat FromDF1 = new SimpleDateFormat(CheckFormat);
                 DF=FromDF1.parse(dateStringFrom);
                 System.out.println(dateStringFrom);
              }
              catch(Exception ex)
              {

                  System.out.println("Date error");

              }

output:- 15/03/2018
         15 Mar 2018

How to assert greater than using JUnit Assert?

You should add Hamcrest-library to your Build Path. It contains the needed Matchers.class which has the lessThan() method.

Dependency as below.

<dependency>
  <groupId>org.hamcrest</groupId>
  <artifactId>hamcrest-library</artifactId>
  <version>1.3</version>
  <scope>test</scope>
</dependency>

Position buttons next to each other in the center of page

jsfiddle: http://jsfiddle.net/mgtoz4d3/

I added a container which contains both buttons. Try this:

CSS:

#button1{
    width: 300px;
    height: 40px;
}
#button2{
    width: 300px;
    height: 40px;
}
#container{
    text-align: center;
}

HTML:

<img src="kingstonunilogo.jpg" alt="uni logo" style="width:180px;height:160px">
<br><br>
<div id="container">
    <button type="button home-button" id="button1" >Home</button>
    <button type="button contact-button" id="button2">Contact Us</button>
</div>

JQuery Ajax Post results in 500 Internal Server Error

I found myself having this error to. I had .htaccess redirect configured in a directory. Well it reroutes ajax calls to ofcourse ($.post(../ajax.php)), so it couldn't find the actual file (resulting in 500 error).

I 'fixed' it by placing the ajax.php in a directory (So .htaccess didn't affect).

Spring,Request method 'POST' not supported

Your user.jsp:

 <form:form action="profile/proffesional" modelAttribute="PROFESSIONAL">
     ---
     ---
    </form:form>

In your controller class:

(make it as a meaning full method name..Hear i think you are insert record in DB.)

@RequestMapping(value = "proffessional", method = RequestMethod.POST)
    public @ResponseBody
    String proffessionalDetails(
            @ModelAttribute UserProfessionalForm professionalForm,
            BindingResult result, Model model) {

        UserProfileVO userProfileVO = new UserProfileVO();

        userProfileVO.setUser(sessionData.getUser());
        userService.saveUserProfile(userProfileVO);
        model.addAttribute("PROFESSIONAL", professionalForm);

        return "Your Professional Details Updated";

    }

What is private bytes, virtual bytes, working set?

The short answer to this question is that none of these values are a reliable indicator of how much memory an executable is actually using, and none of them are really appropriate for debugging a memory leak.

Private Bytes refer to the amount of memory that the process executable has asked for - not necessarily the amount it is actually using. They are "private" because they (usually) exclude memory-mapped files (i.e. shared DLLs). But - here's the catch - they don't necessarily exclude memory allocated by those files. There is no way to tell whether a change in private bytes was due to the executable itself, or due to a linked library. Private bytes are also not exclusively physical memory; they can be paged to disk or in the standby page list (i.e. no longer in use, but not paged yet either).

Working Set refers to the total physical memory (RAM) used by the process. However, unlike private bytes, this also includes memory-mapped files and various other resources, so it's an even less accurate measurement than the private bytes. This is the same value that gets reported in Task Manager's "Mem Usage" and has been the source of endless amounts of confusion in recent years. Memory in the Working Set is "physical" in the sense that it can be addressed without a page fault; however, the standby page list is also still physically in memory but not reported in the Working Set, and this is why you might see the "Mem Usage" suddenly drop when you minimize an application.

Virtual Bytes are the total virtual address space occupied by the entire process. This is like the working set, in the sense that it includes memory-mapped files (shared DLLs), but it also includes data in the standby list and data that has already been paged out and is sitting in a pagefile on disk somewhere. The total virtual bytes used by every process on a system under heavy load will add up to significantly more memory than the machine actually has.

So the relationships are:

Private Bytes are what your app has actually allocated, but include pagefile usage;
Working Set is the non-paged Private Bytes plus memory-mapped files;
Virtual Bytes are the Working Set plus paged Private Bytes and standby list.

There's another problem here; just as shared libraries can allocate memory inside your application module, leading to potential false positives reported in your app's Private Bytes, your application may also end up allocating memory inside the shared modules, leading to false negatives. That means it's actually possible for your application to have a memory leak that never manifests itself in the Private Bytes at all. Unlikely, but possible.

Private Bytes are a reasonable approximation of the amount of memory your executable is using and can be used to help narrow down a list of potential candidates for a memory leak; if you see the number growing and growing constantly and endlessly, you would want to check that process for a leak. This cannot, however, prove that there is or is not a leak.

One of the most effective tools for detecting/correcting memory leaks in Windows is actually Visual Studio (link goes to page on using VS for memory leaks, not the product page). Rational Purify is another possibility. Microsoft also has a more general best practices document on this subject. There are more tools listed in this previous question.

I hope this clears a few things up! Tracking down memory leaks is one of the most difficult things to do in debugging. Good luck.

Vagrant error : Failed to mount folders in Linux guest

(from my comment above)

Following the problem to it's roots: , specifically the part in the comments saying this:

wget https://www.virtualbox.org/download/testcase/VBoxGuestAdditions_4.3.11-93070.iso?? 
sudo cp VBoxGuestAdditions_4.3.11-93070.iso /Applications/VirtualBox.app/Contents/MacOS/VBoxGuestAdditions.iso

After doing that, I have business as usual with all my virtual machines (and their current Vagrantfiles, of course)

When you have to do something in a freshly created virtual machine, to make it work, something is wrong.

jquery mobile background image

For jquery mobile and phonegap this is the correct code:

<style type="text/css">
body {
    background: url(imgage.gif);
    background-repeat:repeat-y;
    background-position:center center;
    background-attachment:scroll;
    background-size:100% 100%;
}
.ui-page {
    background: transparent;
}
.ui-content{
    background: transparent;
}
</style>

SimpleDateFormat and locale based format string

Java 8 Style for a given date

LocalDate today = LocalDate.of(1982, Month.AUGUST, 31);
System.out.println(today.format(DateTimeFormatter.ofLocalizedDate(FormatStyle.MEDIUM).withLocale(Locale.ENGLISH)));
System.out.println(today.format(DateTimeFormatter.ofLocalizedDate(FormatStyle.MEDIUM).withLocale(Locale.FRENCH)));
System.out.println(today.format(DateTimeFormatter.ofLocalizedDate(FormatStyle.MEDIUM).withLocale(Locale.JAPANESE)));

Can pandas automatically recognize dates?

You should add parse_dates=True, or parse_dates=['column name'] when reading, thats usually enough to magically parse it. But there are always weird formats which need to be defined manually. In such a case you can also add a date parser function, which is the most flexible way possible.

Suppose you have a column 'datetime' with your string, then:

from datetime import datetime
dateparse = lambda x: datetime.strptime(x, '%Y-%m-%d %H:%M:%S')

df = pd.read_csv(infile, parse_dates=['datetime'], date_parser=dateparse)

This way you can even combine multiple columns into a single datetime column, this merges a 'date' and a 'time' column into a single 'datetime' column:

dateparse = lambda x: datetime.strptime(x, '%Y-%m-%d %H:%M:%S')

df = pd.read_csv(infile, parse_dates={'datetime': ['date', 'time']}, date_parser=dateparse)

You can find directives (i.e. the letters to be used for different formats) for strptime and strftime in this page.

Custom designing EditText

edit_text.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <solid android:color="#ffffff" />
    <corners android:radius="5dp"/>
    <stroke android:width="2dip" android:color="@color/button_color_submit" />
</shape>

use here

<EditText
 -----
 ------
 android:background="@drawable/edit_text.xml"
/>

View array in Visual Studio debugger?

If you have a large array and only want to see a subsection of the array you can type this into the watch window;

ptr+100,10

to show a list of the 10 elements starting at ptr[100]. Beware that the displayed array subscripts will start at [0], so you will have to remember that ptr[0] is really ptr[100] and ptr[1] is ptr[101] etc.

How can you remove all documents from a collection with Mongoose?

In MongoDB, the db.collection.remove() method removes documents from a collection. You can remove all documents from a collection, remove all documents that match a condition, or limit the operation to remove just a single document.

Source: Mongodb.

If you are using mongo sheel, just do:

db.Datetime.remove({})

In your case, you need:

You didn't show me the delete button, so this button is just an example:

<a class="button__delete"></a>

Change the controller to:

exports.destroy = function(req, res, next) {
    Datetime.remove({}, function(err) {
            if (err) {
                console.log(err)
            } else {
                res.end('success');
            }
        }
    );
};

Insert this ajax delete method in your client js file:

        $(document).ready(function(){
            $('.button__delete').click(function() {
                var dataId = $(this).attr('data-id');

                if (confirm("are u sure?")) {
                    $.ajax({
                        type: 'DELETE',
                        url: '/',
                        success: function(response) {
                            if (response == 'error') {
                                console.log('Err!');
                            }
                            else {
                                alert('Success');
                                location.reload();
                            }
                        }
                    });
                } else {
                    alert('Canceled!');
                }
            });
        });

Fixed position but relative to container

Actually this is possible and the accepted answer only deals with centralising, which is straightforward enough. Also you really don't need to use JavaScript.

This will let you deal with any scenario:

Set everything up as you would if you want to position: absolute inside a position: relative container, and then create a new fixed position div inside the div with position: absolute, but do not set its top and left properties. It will then be fixed wherever you want it, relative to the container.

For example:

_x000D_

/* Main site body */_x000D_
.wrapper {_x000D_
    width: 940px;_x000D_
    margin: 0 auto;_x000D_
    position: relative; /* Ensure absolute positioned child elements are relative to this*/_x000D_
}_x000D_
_x000D_
/* Absolute positioned wrapper for the element you want to fix position */_x000D_
.fixed-wrapper {_x000D_
    width: 220px;_x000D_
    position: absolute;_x000D_
    top: 0;_x000D_
    left: -240px; /* Move this out to the left of the site body, leaving a 20px gutter */_x000D_
}_x000D_
_x000D_
/* The element you want to fix the position of */_x000D_
.fixed {_x000D_
    width: 220px;_x000D_
    position: fixed;_x000D_
    /* Do not set top / left! */_x000D_
}

_x000D_

<div class="wrapper">_x000D_
    <div class="fixed-wrapper">_x000D_
        <div class="fixed">_x000D_
            Content in here will be fixed position, but 240px to the left of the site body._x000D_
        </div>_x000D_
    </div>_x000D_
</div>

_x000D_

Sadly, I was hoping this thread might solve my issue with Android's WebKit rendering box-shadow blur pixels as margins on fixed position elements, but it seems it's a bug.
Anyway, I hope this helps!

Spring MVC - Why not able to use @RequestBody and @RequestParam together

It's too late to answer this question, but it could help for new readers, It seems version issues. I ran all these tests with spring 4.1.4 and found that the order of @RequestBody and @RequestParam doesn't matter.

same as your result
same as your result
gave body= "name=abc", and name = "abc"
Same as 3.
body ="name=abc", name = "xyz,abc"
same as 5.

How to hide a div with jQuery?

Easy:

$('#myDiv').hide();

http://api.jquery.com/hide/

Google reCAPTCHA: How to get user response and validate in the server side?

Hi curious you can validate your google recaptcha at client side also 100% work for me to verify your google recaptcha just see below code
This code at the html body:

 <div class="g-recaptcha" id="rcaptcha" style="margin-left: 90px;" data-sitekey="my_key"></div>
 <span id="captcha" style="margin-left:100px;color:red" />

This code put at head section on call get_action(this) method form button:

function get_action(form) {

var v = grecaptcha.getResponse();
if(v.length == 0)
{
    document.getElementById('captcha').innerHTML="You can't leave Captcha Code empty";
    return false;
}
 if(v.length != 0)
 {
    document.getElementById('captcha').innerHTML="Captcha completed";
    return true; 
 }
}

How to avoid the "Windows Defender SmartScreen prevented an unrecognized app from starting warning"

After clicking on Properties of any installer(.exe) which block your application to install (Windows Defender SmartScreen prevented an unrecognized app ) for that issue i found one solution

Right click on installer(.exe)

Select properties option.

Click on checkbox to check Unblock at the bottom of Properties.

This solution work for Heroku CLI (heroku-x64) installer(.exe)

How do I do a Date comparison in Javascript?

function fn_DateCompare(DateA, DateB) {     // this function is good for dates > 01/01/1970

    var a = new Date(DateA);
    var b = new Date(DateB);

    var msDateA = Date.UTC(a.getFullYear(), a.getMonth()+1, a.getDate());
    var msDateB = Date.UTC(b.getFullYear(), b.getMonth()+1, b.getDate());

    if (parseFloat(msDateA) < parseFloat(msDateB))
      return -1;  // lt
    else if (parseFloat(msDateA) == parseFloat(msDateB))
      return 0;  // eq
    else if (parseFloat(msDateA) > parseFloat(msDateB))
      return 1;  // gt
    else
      return null;  // error
}

How to call a asp:Button OnClick event using JavaScript?

If you're open to using jQuery:

<script type="text/javascript">
 function fncsave()
 {
    $('#<%= savebtn.ClientID %>').click();
 }
</script>

Also, if you are using .NET 4 or better you can make the ClientIDMode == static and simplify the code:

<script type="text/javascript">
 function fncsave()
 {
    $("#savebtn").click();
 }
</script>

Reference: MSDN Article for Control.ClientIDMode

Heroku + node.js error (Web process failed to bind to $PORT within 60 seconds of launch)

The error happens when Heroku failed to bind the port or hostname at server.listen(port, [host], [backlog], [callback]).

What Heroku requires is .listen(process.env.PORT) or .listen(process.env.PORT, '0.0.0.0')

So more generically, to support other environments, use this:

var server_port = process.env.YOUR_PORT || process.env.PORT || 80;
var server_host = process.env.YOUR_HOST || '0.0.0.0';
server.listen(server_port, server_host, function() {
    console.log('Listening on port %d', server_port);
});

How do I remove a file from the FileList

Thanks @Nicholas Anderson simple and straight , here is your code applied and working at my code using jquery.

HTML .

<input class="rangelog btn border-aero" id="file_fr" name="file_fr[]" multiple type="file" placeholder="{$labels_helpfiles_placeholder_file}">
<span style="cursor: pointer; cursor: hand;" onclick="cleanInputs($('#file_fr'))"><i class="fa fa-trash"></i> Empty chosen files</span>

JS CODE

   function cleanInputs(fileEle){
    $(fileEle).val("");
    var parEle = $(fileEle).parent();
    var newEle = $(fileEle).clone()
    $(fileEle).remove();
    $(parEle).prepend(newEle);
}

Placing an image to the top right corner - CSS

You can just do it like this:

#content {
    position: relative;
}
#content img {
    position: absolute;
    top: 0px;
    right: 0px;
}

<div id="content">
    <img src="images/ribbon.png" class="ribbon"/>
    <div>some text...</div>
</div>

How to delete a folder with files using Java

If you have subfolders, you will find troubles with the Cemron answers. so you should create a method that works like this:

private void deleteTempFile(File tempFile) {
        try
        {
            if(tempFile.isDirectory()){
               File[] entries = tempFile.listFiles();
               for(File currentFile: entries){
                   deleteTempFile(currentFile);
               }
               tempFile.delete();
            }else{
               tempFile.delete();
            }
        getLogger().info("DELETED Temporal File: " + tempFile.getPath());
        }
        catch(Throwable t)
        {
            getLogger().error("Could not DELETE file: " + tempFile.getPath(), t);
        }
    }

How to hide elements without having them take space on the page?

display:none to hide and set display:block to show.

How to enter in a Docker container already running with a new TTY

With docker 1.3, there is a new command docker exec. This allows you to enter a running container:

docker exec -it [container-id] bash

Manually install Gradle and use it in Android Studio

(There are 2 solutions mentioned in existing answers that might work, but the preferred one - manually download gradle for gradlew, is lack of essential details, and cause it fail. So, I would add a summary with missing details to save the unnecessary time wasted, in case others encounter into the same issue.)

There are 2 possible solutions:

Solution A: Use location gradle, and delete gradlew related files. (not recommend)

Refer to this answer from this post: https://stackoverflow.com/a/29198101/

Tips:

I tried, it works, though this is not suggested for gradle use in general.
And, with this solution, each time open project, android-studio will ask to confirm whether to use gradlew instead, it's kinda annoying.

Solution B: Download gradle distribution manually for gradlew. (recommended)

Android Studio will download gradle to sub dir named by a hash.
To download manually, need to download to the exact sub dir named by the hash.

Steps:

Get the hash.
- Start android-studio.
- Create a basic project.
- Then it will create the hash, and start to download gradle.
  e.g .gradle/wrapper/dists/gradle-4.10.1-all/455itskqi2qtf0v2sja68alqd/
- Close android-studio.
- Find the download process, by android-studio.
  e.g ps -aux grep | android
- Kill all the related android processes.
- Remove the blank project.
Download gradle by hand.
- Go to the hash folder.
  e.g .gradle/wrapper/dists/gradle-4.10.1-all/455itskqi2qtf0v2sja68alqd/
- There is a partly download file.
  e.g gradle-4.10.1-all.zip.part
- Download the exact version by hand.
  from website: https://services.gradle.org/distributions/
  e.g https://services.gradle.org/distributions/gradle-4.10.1-all.zip
- Remove the *.part file.
- And copy the download file there instead.
  e.g .gradle/wrapper/dists/gradle-4.10.1-all/455itskqi2qtf0v2sja68alqd/gradle-4.10.1-all.zip
Start Android Studio and try again.
- Create a new blank project again.
- Then it shouldn't need to download gradle again.
- It will uncompress gradle in the the same dir.
  e.g .gradle/wrapper/dists/gradle-4.10.1-all/455itskqi2qtf0v2sja68alqd/gradle-4.10.1/
- And starts to sync dependencies, indexing, and build.

Tips:

After restart Android Studio & creating blank project again, if you see it says waiting for other process to download the distribution.
That means you didn't kill the previous download process, kill it first, then remove blank project, then create a new project to confirm again.
Each version of Android Studio might use different gradle version, thus might need to repeat this process once, when Android Studio is upgraded.

BTW:

Here is the dir layout on my Linux
(For Android Studio 3.3.1, which use gradle 4.10.1)

eric@eric-pc:~/.gradle/wrapper$ tree -L 4

.
+-- dists
    +-- gradle-4.10.1-all
        +-- 455itskqi2qtf0v2sja68alqd
            +-- gradle-4.10.1
            +-- gradle-4.10.1-all.zip
            +-- gradle-4.10.1-all.zip.lck
            +-- gradle-4.10.1-all.zip.ok

Suggestions to Android-Studio

Since it's so slow when download gradle distrbution within Android Studio.
It's better to provide an option to choose local gradle installation dir or .zip file to be used by gradlew.

Display A Popup Only Once Per User

You can use removeItem() class of localStorage to destroy that key on browser close with:

window.onbeforeunload = function{
    localStorage.removeItem('your key');
};

SQLite add Primary Key

I tried to add the primary key afterwards by changing the sqlite_master table directly. This trick seems to work. It is a hack solution of course.

In short: create a regular (unique) index on the table, then make the schema writable and change the name of the index to the form reserved by sqlite to identify a primary key index, (i.e. sqlite_autoindex_XXX_1, where XXX is the table name) and set the sql string to NULL. At last change the table definition itself. One pittfal: sqlite does not see the index name change until the database is reopened. This seems like a bug, but not a severe one (even without reopening the database, you can still use it).

Suppose the table looks like:

CREATE TABLE tab1(i INTEGER, j INTEGER, t TEXT);

Then I did the following:

BEGIN;
CREATE INDEX pk_tab1 ON tab1(i,j);
pragma writable_schema=1;
UPDATE sqlite_master SET name='sqlite_autoindex_tab1_1',sql=null WHERE name='pk_tab1';
UPDATE sqlite_master SET sql='CREATE TABLE tab1(i integer,j integer,t text,primary key(i,j))' WHERE name='tab1';
COMMIT;

Some tests (in sqlite shell):

sqlite> explain query plan select * from tab1 order by i,j;
0|0|0|SCAN TABLE tab1 USING INDEX sqlite_autoindex_tab1_1
sqlite> drop index sqlite_autoindex_tab1_1;
Error: index associated with UNIQUE or PRIMARY KEY constraint cannot be dropped

Kubernetes service external ip pending

If you are not using GCE or EKS (you used kubeadm) you can add an externalIPs spec to your service YAML. You can use the IP associated with your node's primary interface such as eth0. You can then access the service externally, using the external IP of the node.

...
spec:
  type: LoadBalancer
  externalIPs:
  - 192.168.0.10

How to use DbContext.Database.SqlQuery<TElement>(sql, params) with stored procedure? EF Code First CTP5

I had the same error message when I was working with calling a stored procedure that takes two input parameters and returns 3 values using SELECT statement and I solved the issue like below in EF Code First Approach

 SqlParameter @TableName = new SqlParameter()
        {
            ParameterName = "@TableName",
            DbType = DbType.String,
            Value = "Trans"
        };

SqlParameter @FieldName = new SqlParameter()
        {
            ParameterName = "@FieldName",
            DbType = DbType.String,
            Value = "HLTransNbr"
        };


object[] parameters = new object[] { @TableName, @FieldName };

List<Sample> x = this.Database.SqlQuery<Sample>("EXEC usp_NextNumberBOGetMulti @TableName, @FieldName", parameters).ToList();


public class Sample
{
    public string TableName { get; set; }
    public string FieldName { get; set; }
    public int NextNum { get; set; }
}

UPDATE: It looks like with SQL SERVER 2005 missing EXEC keyword is creating problem. So to allow it to work with all SQL SERVER versions I updated my answer and added EXEC in below line

 List<Sample> x = this.Database.SqlQuery<Sample>(" EXEC usp_NextNumberBOGetMulti @TableName, @FieldName", param).ToList();

How to check if an object implements an interface?

If you want a method like public void doSomething([Object implements Serializable]) you can just type it like this public void doSomething(Serializable serializableObject). You can now pass it any object that implements Serializable but using the serializableObject you only have access to the methods implemented in the object from the Serializable interface.

Select Multiple Fields from List in Linq

public class Student
{
    public string Name { set; get; }
    public int ID { set; get; }
}

class Program
{
  static void Main(string[] args)
    {
        Student[] students =
        {
        new Student { Name="zoyeb" , ID=1},
        new Student { Name="Siddiq" , ID=2},
        new Student { Name="sam" , ID=3},
        new Student { Name="james" , ID=4},
        new Student { Name="sonia" , ID=5}
        };

        var studentCollection = from s in students select new { s.ID , s.Name};

        foreach (var student in studentCollection)
        {
            Console.WriteLine(student.Name);
            Console.WriteLine(student.ID);
        }
    }
}

How can I set a website image that will show as preview on Facebook?

1. Include the Open Graph XML namespace extension to your HTML declaration

<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:fb="http://ogp.me/ns/fb#">

2. Inside your <head></head> use the following meta tag to define the image you want to use

<meta property="og:image" content="fully_qualified_image_url_here" />

Read more about open graph protocol here.

After doing the above, use the Facebook "Object Debugger" if the image does not show up correctly. Also note the first time shared it still won't show up unless height and width are also specified, see Share on Facebook - Thumbnail not showing for the first time

How to redirect cin and cout to files?

If your input file is in.txt, you can use freopen to set stdin file as in.txt

freopen("in.txt","r",stdin);

if you want to do the same with your output:

freopen("out.txt","w",stdout);

this will work for std::cin (if using c++), printf, etc...

This will also help you in debugging your code in clion, vscode

Converting file size in bytes to human-readable string

For those who use Angular, there's a package called angular-pipes that has a pipe for this:

File

import { BytesPipe } from 'angular-pipes';

Usage

{{ 150 | bytes }} <!-- 150 B -->
{{ 1024 | bytes }} <!-- 1 KB -->
{{ 1048576 | bytes }} <!-- 1 MB -->
{{ 1024 | bytes: 0 : 'KB' }} <!-- 1 MB -->
{{ 1073741824 | bytes }} <!-- 1 GB -->
{{ 1099511627776 | bytes }} <!-- 1 TB -->
{{ 1073741824 | bytes : 0 : 'B' : 'MB' }} <!-- 1024 MB -->

Link to the docs.

Invoking modal window in AngularJS Bootstrap UI using JavaScript

Different version similar to the one offered by Maxim Shoustin

I liked the answer but the part that bothered me was the use of <script id="..."> as a container for the modal's template.

I wanted to place the modal's template in a hidden <div> and bind the inner html with a scope variable called modal_html_template mainly because i think it more correct (and more comfortable to process in WebStorm/PyCharm) to place the template's html inside a <div> instead of <script id="...">

this variable will be used when calling $modal({... 'template': $scope.modal_html_template, ...})

in order to bind the inner html, i created inner-html-bind which is a simple directive

check out the example plunker

<div ng-controller="ModalDemoCtrl">

    <div inner-html-bind inner-html="modal_html_template" class="hidden">
        <div class="modal-header">
            <h3>I'm a modal!</h3>
        </div>
        <div class="modal-body">
            <ul>
                <li ng-repeat="item in items">
                    <a ng-click="selected.item = item">{{ item }}</a>
                </li>
            </ul>
            Selected: <b>{{ selected.item }}</b>
        </div>
        <div class="modal-footer">
            <button class="btn btn-primary" ng-click="ok()">OK</button>
            <button class="btn btn-warning" ng-click="cancel()">Cancel</button>
        </div>
    </div>

    <button class="btn" ng-click="open()">Open me!</button>
    <div ng-show="selected">Selection from a modal: {{ selected }}</div>
</div>

inner-html-bind directive:

app.directive('innerHtmlBind', function() {
  return {
    restrict: 'A',
    scope: {
      inner_html: '=innerHtml'
    },
    link: function(scope, element, attrs) {
      scope.inner_html = element.html();
    }
  }
});

How to add 'ON DELETE CASCADE' in ALTER TABLE statement

You can not add ON DELETE CASCADE to an already existing constraint. You will have to drop and re-create the constraint. The documentation shows that the MODIFY CONSTRAINT clause can only modify the state of a constraint (i-e: ENABLED/DISABLED...).

Get all non-unique values (i.e.: duplicate/more than one occurrence) in an array

Yet another way by using underscore. Numbers is the source array and dupes has possible duplicate values.

var itemcounts = _.countBy(numbers, function (n) { return n; });
var dupes = _.reduce(itemcounts, function (memo, item, idx) {
    if (item > 1)
        memo.push(idx);
    return memo;
}, []);

jquery multiple checkboxes array

var checkedString = $('input:checkbox:checked.name').map(function() { return this.value; }).get().join();

Replace a newline in TSQL

In SQL Server 2017 & later, use Trim

Select Trim(char(10) + char(13) from @str)

it trims on starting and ending, not in the middle
the order of \r and \n does not matter

I use it to trim special characters for a file name

Select Trim(char(10) + char(13) + ' *<>' from @fileName)

What does the M stand for in C# Decimal literal notation?

It means it's a decimal literal, as others have said. However, the origins are probably not those suggested elsewhere in this answer. From the C# Annotated Standard (the ECMA version, not the MS version):

The decimal suffix is M/m since D/d was already taken by double. Although it has been suggested that M stands for money, Peter Golde recalls that M was chosen simply as the next best letter in decimal.

A similar annotation mentions that early versions of C# included "Y" and "S" for byte and short literals respectively. They were dropped on the grounds of not being useful very often.

How to detect DataGridView CheckBox event change?

It's all about editing the cell, the problem that is the cell didn't edited actually, so you need to save The changes of the cell or the row to get the event when you click the check box so you can use this function:

datagridview.CommitEdit(DataGridViewDataErrorContexts.CurrentCellChange)

with this you can use it even with a different event.

How to enable bulk permission in SQL Server

Try this:

USE master;

GO;
 
GRANT ADMINISTER BULK OPERATIONS TO shira;

How do I ignore files in Subversion?

As nobody seems to have mentioned it...

svn propedit svn:ignore .

Then edit the contents of the file to specify the patterns to ignore, exit the editor and you're all done.

How do I get the project basepath in CodeIgniter

Following are the build-in constants you can use as per your requirements for getting the paths in Codeigniter:

EXT: The PHP file extension

FCPATH: Path to the front controller (this file) (root of CI)

SELF: The name of THIS file (index.php)

BASEPATH: Path to the system folder

APPPATH: The path to the “application” folder

Thanks.

CSS overflow-x: visible; and overflow-y: hidden; causing scrollbar issue

I've run into this issue when trying to build a fixed positioned sidebar with both vertically scrollable content and nested absolute positioned children to be displayed outside sidebar boundaries.

My approach consisted of separately apply:

an overflow: visible property to the sidebar element
an overflow-y: auto property to sidebar inner wrapper

Please check the example below or an online codepen.

_x000D_

html {_x000D_
  min-height: 100%;_x000D_
}_x000D_
body {_x000D_
  min-height: 100%;_x000D_
  background: linear-gradient(to bottom, white, DarkGray 80%);_x000D_
  margin: 0;_x000D_
  padding: 0;_x000D_
}_x000D_
_x000D_
.sidebar {_x000D_
  position: fixed;_x000D_
  top: 0;_x000D_
  right: 0;_x000D_
  height: 100%;_x000D_
  width: 200px;_x000D_
  overflow: visible;  /* Just apply overflow-x */_x000D_
  background-color: DarkOrange;_x000D_
}_x000D_
_x000D_
.sidebarWrapper {_x000D_
  padding: 10px;_x000D_
  overflow-y: auto;   /* Just apply overflow-y */_x000D_
  height: 100%;_x000D_
  width: 100%;_x000D_
}_x000D_
_x000D_
.element {_x000D_
  position: absolute;_x000D_
  top: 0;_x000D_
  right: 100%;_x000D_
  background-color: CornflowerBlue;_x000D_
  padding: 10px;_x000D_
  width: 200px;_x000D_
}

_x000D_

<p>Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt explicabo. Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit qui in ea voluptate velit esse quam nihil molestiae consequatur, vel illum qui dolorem eum fugiat quo voluptas nulla pariatur?</p>_x000D_
<div class="sidebar">_x000D_
  <div class="sidebarWrapper">_x000D_
    <div class="element">_x000D_
      I'm a sidebar child element but I'm able to horizontally overflow its boundaries._x000D_
    </div>_x000D_
    <p>This is a 200px width container with optional vertical scroll.</p>_x000D_
    <p>Sed ut perspiciatis unde omnis iste natus error sit voluptatem accusantium doloremque laudantium, totam rem aperiam, eaque ipsa quae ab illo inventore veritatis et quasi architecto beatae vitae dicta sunt explicabo. Nemo enim ipsam voluptatem quia voluptas sit aspernatur aut odit aut fugit, sed quia consequuntur magni dolores eos qui ratione voluptatem sequi nesciunt. Neque porro quisquam est, qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit, sed quia non numquam eius modi tempora incidunt ut labore et dolore magnam aliquam quaerat voluptatem. Ut enim ad minima veniam, quis nostrum exercitationem ullam corporis suscipit laboriosam, nisi ut aliquid ex ea commodi consequatur? Quis autem vel eum iure reprehenderit qui in ea voluptate velit esse quam nihil molestiae consequatur, vel illum qui dolorem eum fugiat quo voluptas nulla pariatur?</p>_x000D_
  </div>_x000D_
</div>

_x000D_

How to recompile with -fPIC

Before compiling make sure that "rules.mk" file is included properly in Makefile or include it explicitly by:

"source rules.mk"

How do I use extern to share variables between source files?

The correct interpretation of extern is that you tell something to the compiler. You tell the compiler that, despite not being present right now, the variable declared will somehow be found by the linker (typically in another object (file)). The linker will then be the lucky guy to find everything and put it together, whether you had some extern declarations or not.

Array initialization syntax when not in a declaration

Why is this blocked by Java?

You'd have to ask the Java designers. There might be some subtle grammatical reason for the restriction. Note that some of the array creation / initialization constructs were not in Java 1.0, and (IIRC) were added in Java 1.1.

But "why" is immaterial ... the restriction is there, and you have to live with it.

I know how to work around it, but from time to time it would be simpler.

You can write this:

AClass[] array;
...
array = new AClass[]{object1, object2};

How to convert datatype:object to float64 in python?

X = np.array(X, dtype=float)

You can use this to convert to array of float in python 3.7.6

Why was the name 'let' chosen for block-scoped variable declarations in JavaScript?

Let is a mathematical statement that was adopted by early programming languages like Scheme and Basic. Variables are considered low level entities not suitable for higher levels of abstraction, thus the desire of many language designers to introduce similar but more powerful concepts like in Clojure, F#, Scala, where let might mean a value, or a variable that can be assigned, but not changed, which in turn lets the compiler catch more programming errors and optimize code better.

JavaScript has had var from the beginning, so they just needed another keyword, and just borrowed from dozens of other languages that use let already as a traditional keyword as close to var as possible, although in JavaScript let creates block scope local variable instead.

Can I call jQuery's click() to follow an <a> link if I haven't bound an event handler to it with bind or click already?

If you need this feature for one case or very few cases (your whole application is not requiring this feature). I would rather leave jQuery as is (for many reasons, including being able to update to newer versions, CDN, etc.) and have the following workaround:

// For modern browsers
$(ele).trigger("click");

// Relying on Paul Irish's conditional class names,
// <https://www.paulirish.com/2008/conditional-stylesheets-vs-css-hacks-answer-neither/>
// (via HTML5 Boilerplate, <https://html5boilerplate.com/>) where
// each Internet Explorer version gets a class of its version
$("html.ie7").length && (function(){
    var eleOnClickattr = $(ele).attr("onclick")
    eval(eleOnClickattr);
})()

Simple insecure two-way data "obfuscation"?

I combined what I found the best from several answers and comments.

Random initialization vector prepended to crypto text (@jbtule)
Use TransformFinalBlock() instead of MemoryStream (@RenniePet)
No pre-filled keys to avoid anyone copy & pasting a disaster
Proper dispose and using patterns

Code:

/// <summary>
/// Simple encryption/decryption using a random initialization vector
/// and prepending it to the crypto text.
/// </summary>
/// <remarks>Based on multiple answers in http://stackoverflow.com/questions/165808/simple-two-way-encryption-for-c-sharp </remarks>
public class SimpleAes : IDisposable
{
    /// <summary>
    ///     Initialization vector length in bytes.
    /// </summary>
    private const int IvBytes = 16;

    /// <summary>
    ///     Must be exactly 16, 24 or 32 bytes long.
    /// </summary>
    private static readonly byte[] Key = Convert.FromBase64String("FILL ME WITH 24 (2 pad chars), 32 OR 44 (1 pad char) RANDOM CHARS"); // Base64 has a blowup of four-thirds (33%)

    private readonly UTF8Encoding _encoder;
    private readonly ICryptoTransform _encryptor;
    private readonly RijndaelManaged _rijndael;

    public SimpleAes()
    {
        _rijndael = new RijndaelManaged {Key = Key};
        _rijndael.GenerateIV();
        _encryptor = _rijndael.CreateEncryptor();
        _encoder = new UTF8Encoding();
    }

    public string Decrypt(string encrypted)
    {
        return _encoder.GetString(Decrypt(Convert.FromBase64String(encrypted)));
    }

    public void Dispose()
    {
        _rijndael.Dispose();
        _encryptor.Dispose();
    }

    public string Encrypt(string unencrypted)
    {
        return Convert.ToBase64String(Encrypt(_encoder.GetBytes(unencrypted)));
    }

    private byte[] Decrypt(byte[] buffer)
    {
        // IV is prepended to cryptotext
        byte[] iv = buffer.Take(IvBytes).ToArray();
        using (ICryptoTransform decryptor = _rijndael.CreateDecryptor(_rijndael.Key, iv))
        {
            return decryptor.TransformFinalBlock(buffer, IvBytes, buffer.Length - IvBytes);
        }
    }

    private byte[] Encrypt(byte[] buffer)
    {
        // Prepend cryptotext with IV
        byte [] inputBuffer = _encryptor.TransformFinalBlock(buffer, 0, buffer.Length); 
        return _rijndael.IV.Concat(inputBuffer).ToArray();
    }
}

Update 2015-07-18: Fixed mistake in private Encrypt() method by comments of @bpsilver and @Evereq. IV was accidentally encrypted, is now prepended in clear text as expected by Decrypt().

Android: how to parse URL String with spaces to URI object?

I wrote this function:

public static String encode(@NonNull String uriString) {
    if (TextUtils.isEmpty(uriString)) {
        Assert.fail("Uri string cannot be empty!");
        return uriString;
    }
    // getQueryParameterNames is not exist then cannot iterate on queries
    if (Build.VERSION.SDK_INT < 11) {
        return uriString;
    }

    // Check if uri has valid characters
    // See https://tools.ietf.org/html/rfc3986
    Pattern allowedUrlCharacters = Pattern.compile("([A-Za-z0-9_.~:/?\\#\\[\\]@!$&'()*+,;" +
            "=-]|%[0-9a-fA-F]{2})+");
    Matcher matcher = allowedUrlCharacters.matcher(uriString);
    String validUri = null;
    if (matcher.find()) {
        validUri = matcher.group();
    }
    if (TextUtils.isEmpty(validUri) || uriString.length() == validUri.length()) {
        return uriString;
    }

    // The uriString is not encoded. Then recreate the uri and encode it this time
    Uri uri = Uri.parse(uriString);
    Uri.Builder uriBuilder = new Uri.Builder()
            .scheme(uri.getScheme())
            .authority(uri.getAuthority());
    for (String path : uri.getPathSegments()) {
        uriBuilder.appendPath(path);
    }
    for (String key : uri.getQueryParameterNames()) {
        uriBuilder.appendQueryParameter(key, uri.getQueryParameter(key));
    }
    String correctUrl = uriBuilder.build().toString();
    return correctUrl;
}

Can regular JavaScript be mixed with jQuery?

Yes, they're both JavaScript, you can use whichever functions are appropriate for the situation.

In this case you can just put the code in a document.ready handler, like this:

$(function() {
  var canvas = document.getElementById("canvas");
  if (canvas.getContext) {
    var ctx = canvas.getContext("2d");

    ctx.fillStyle = "rgb(200,0,0)";
    ctx.fillRect (10, 10, 55, 50);

    ctx.fillStyle = "rgba(0, 0, 200, 0.5)";
    ctx.fillRect (30, 30, 55, 50);
  }
});

Microsoft.ACE.OLEDB.12.0 provider is not registered

I've got the same error on a fully updated Windows Vista Family 64bit with a .NET application that I've compiled to 32 bit only - the program is installed in the programx86 folder on 64 bit machines. It fails with this error message even with 2007 access database provider installed, with/wiothout the SP2 of the same installed, IIS installed and app pool set for 32bit app support... yes I've tried every solution everywhere and still no success.

I switched my app to ACE OLE DB.12.0 because JET4.0 was failing on 64bit machines - and it's no better :-/ The most promising thread I've found was this:

http://ellisweb.net/2010/01/connecting-to-excel-and-access-files-using-net-on-a-64-bit-server/

but when you try to install the 64 bit "2010 Office System Driver Beta: Data Connectivity Components" it tells you that you can't install the 64 bit version without uninstalling all 32bit office applications... and installing the 32 bit version of 2010 Office System Driver Beta: Data Connectivity Components doesn't solve the initial problem, even with "Microsoft.ACE.OLEDB.12.0" as provider instead of "Microsoft.ACE.OLEDB.14.0" which that page (and others) recommend.

My next attempt will be to follow this post:

The issue is due to the wrong flavor of OLEDB32.DLL and OLEDB32r.DLL being registered on the server. If the 64 bit versions are registered, they need to be unregistered, and then the 32 bit versions registered instead. To fix this, unregister the versions located in %Program Files%/Common Files/System/OLE DB. Then register the versions at the same path but in the %Program Files (x86)% directory.

Has anyone else had so much trouble with both JET4.0 and OLEDB ACE providers on 64 bit machines? Has anyone found a solution if none of the others work?

What is the best method of handling currency/money?

Common practice for handling currency is to use decimal type. Here is a simple example from "Agile Web Development with Rails"

add_column :products, :price, :decimal, :precision => 8, :scale => 2

This will allow you to handle prices from -999,999.99 to 999,999.99
You may also want to include a validation in your items like

def validate 
  errors.add(:price, "should be at least 0.01") if price.nil? || price < 0.01 
end

to sanity-check your values.

Java getting the Enum name given the Enum Value

Try, the following code..

    @Override
    public String toString() {
    return this.name();
    }

Android: How to detect double-tap?

combining "Bughi" "DoubleClickListner" and "Jayant Arora" Timer in one contained class:

public abstract class DoubleClickListener implements OnClickListener {

    private Timer timer = null;  //at class level;
    private int DELAY   = 400;

    private static final long DOUBLE_CLICK_TIME_DELTA = 300;//milliseconds

    long lastClickTime = 0;

    @Override
    public void onClick(View v) {
        long clickTime = System.currentTimeMillis();
        if (clickTime - lastClickTime < DOUBLE_CLICK_TIME_DELTA){
            processDoubleClickEvent(v);
        } else {
            processSingleClickEvent(v);
        }
        lastClickTime = clickTime;
    }



    public void processSingleClickEvent(final View v){

        final Handler handler=new Handler();
        final Runnable mRunnable=new Runnable(){
            public void run(){
                onSingleClick(v); //Do what ever u want on single click

            }
        };

        TimerTask timertask=new TimerTask(){
            @Override
            public void run(){
                handler.post(mRunnable);
            }
        };
        timer=new Timer();
        timer.schedule(timertask,DELAY);

    }

    public void processDoubleClickEvent(View v){
        if(timer!=null)
        {
            timer.cancel(); //Cancels Running Tasks or Waiting Tasks.
            timer.purge();  //Frees Memory by erasing cancelled Tasks.
        }
        onDoubleClick(v);//Do what ever u want on Double Click
    }

    public abstract void onSingleClick(View v);

    public abstract void onDoubleClick(View v);
}

and can be called as :

view.setOnClickListener(new DoubleClickListener() {

            @Override
            public void onSingleClick(View v) {

            }

            @Override
            public void onDoubleClick(View v) {

            }
        });

How to write files to assets folder or raw folder in android?

You Can't write JSON file while in assets. as already described assets are read-only. But you can copy assets (json file/anything else in assets ) to local storage of mobile and then edit(write/read) from local storage. More storage options like shared Preference(for small data) and sqlite database(for large data) are available.

Correct MIME Type for favicon.ico?

When you're serving an .ico file to be used as a favicon, it doesn't matter. All major browsers recognize both mime types correctly. So you could put:

<!-- IE -->
<link rel="shortcut icon" type="image/x-icon" href="favicon.ico" />
<!-- other browsers -->
<link rel="icon" type="image/x-icon" href="favicon.ico" />

or the same with image/vnd.microsoft.icon, and it will work with all browsers.

Note: There is no IANA specification for the MIME-type image/x-icon, so it does appear that it is a little more unofficial than image/vnd.microsoft.icon.

The only case in which there is a difference is if you were trying to use an .ico file in an <img> tag (which is pretty unusual). Based on previous testing, some browsers would only display .ico files as images when they were served with the MIME-type image/x-icon. More recent tests show: Chromium, Firefox and Edge are fine with both content types, IE11 is not. If you can, just avoid using ico files as images, use png.

How do I set GIT_SSL_NO_VERIFY for specific repos only?

On Linux, if you call this inside the git repository folder:

git config http.sslVerify false

this will add sslVerify = false in the [http] section of the config file in the .git folder, which can also be the solution, if you want to add this manually with nano .git/config:

...
[http]
  sslVerify = false

How to import an excel file in to a MySQL database

Another useful tool, and as a MySQL front-end replacement, is Toad for MySQL. Sadly, no longer supported by Quest, but a brilliant IDE for MySQL, with IMPORT and EXPORT wizards, catering for most file types.

How to send a GET request from PHP?

Remember that if you are using a proxy you need to do a little trick in your php code:

(PROXY WITHOUT AUTENTICATION EXAMPLE)

<?php
$aContext = array(
    'http' => array(
        'proxy' => 'proxy:8080',
        'request_fulluri' => true,
    ),
);
$cxContext = stream_context_create($aContext);

$sFile = file_get_contents("http://www.google.com", False, $cxContext);

echo $sFile;
?>

HTTP Status 404 - The requested resource (/) is not available

Following steps helped me solve the issue.

In the eclipse right click on server and click on properties.
If Location is set workspace/metadata click on switch location and so that it refers to /servers/tomcatv7server at localhost.server
Save and close
Next double click on server
Under server locations mostly it would be selected as use workspace metadata Instead, select use tomcat installation
Save changes
Restart server and verify localhost:8080 works.

Get user profile picture by Id

Here, this api allows you to get fb, google and twitter profile pics easily

https://www.avatars.io/

It's an API that returns the profile image when given a username for a variety of social networks including Twitter, Facebook, Instagram, and gravatar. It has libraries for iOS, Android, Ruby, Node, PHP, Python, and JavaScript.

Setting POST variable without using form

Yes, simply set it to another value:

$_POST['text'] = 'another value';

This will override the previous value corresponding to text key of the array. The $_POST is superglobal associative array and you can change the values like a normal PHP array.

Caution: This change is only visible within the same PHP execution scope. Once the execution is complete and the page has loaded, the $_POST array is cleared. A new form submission will generate a new $_POST array.

If you want to persist the value across form submissions, you will need to put it in the form as an input tag's value attribute or retrieve it from a data store.

Cannot create a connection to data source Error (rsErrorOpeningConnection) in SSRS

I had a similar problem, and being the newbie that I am it took me a while to figure out but I learned the user must have a login in SSMS. I created the logins with the following parameters:

Under Server Roles - check sysadmin
Under User Mapping - I selected the database and the report server. For each I checked datareader and datawriter
Under Securables - I checked anything that would allow the user to connect to the database and view anything
I also found that one of the existing logins had denydatareader and denydatawriter checked. Once I removed these it worked.

I'm not saying this is the best way to do it, just what worked for me. Hope this helps

How to convert String object to Boolean Object?

public static boolean stringToBool(String s) {
        s = s.toLowerCase();
        Set<String> trueSet = new HashSet<String>(Arrays.asList("1", "true", "yes"));
        Set<String> falseSet = new HashSet<String>(Arrays.asList("0", "false", "no"));

        if (trueSet.contains(s))
            return true;
        if (falseSet.contains(s))
            return false;

        throw new IllegalArgumentException(s + " is not a boolean.");
    }

My way to convert string to boolean.

VB.NET Empty String Array

The array you created by Dim s(0) As String IS NOT EMPTY

In VB.Net, the subscript you use in the array is index of the last element. VB.Net by default starts indexing at 0, so you have an array that already has one element.

You should instead try using System.Collections.Specialized.StringCollection or (even better) System.Collections.Generic.List(Of String). They amount to pretty much the same thing as an array of string, except they're loads better for adding and removing items. And let's be honest: you'll rarely create an empty string array without wanting to add at least one element to it.

If you really want an empty string array, declare it like this:

Dim s As String()

Dim t() As String

Why did a network-related or instance-specific error occur while establishing a connection to SQL Server?

Your connection string was probably overriden when you copied your new website version on the server. Please check the connection string in web.config and see if it is valid.

How to use variables in a command in sed?

Say:

sed "s|\$ROOT|${HOME}|" abc.sh

Note:

Use double quotes so that the shell would expand variables.
Use a separator different than / since the replacement contains /
Escape the $ in the pattern since you don't want to expand it.

EDIT: In order to replace all occurrences of $ROOT, say

sed "s|\$ROOT|${HOME}|g" abc.sh

How do I specify different layouts for portrait and landscape orientations?

Create a layout-land directory and put the landscape version of your layout XML file in that directory.

GridView must be placed inside a form tag with runat="server" even after the GridView is within a form tag

Here is My Code

protected void btnExcel_Click(object sender, ImageClickEventArgs e)
    {
        if (gvDetail.Rows.Count > 0)
        {
            System.IO.StringWriter stringWrite1 = new System.IO.StringWriter();
            System.Web.UI.HtmlTextWriter htmlWrite1 = new HtmlTextWriter(stringWrite1);
            gvDetail.RenderControl(htmlWrite1);

            gvDetail.AllowPaging = false;
            Search();
            sh.ExportToExcel(gvDetail, "Report");
        }
    }

    public override void VerifyRenderingInServerForm(Control control)
    {
        /* Confirms that an HtmlForm control is rendered for the specified ASP.NET
           server control at run time. */
    }

How to resize Twitter Bootstrap modal dynamically based on the content

I had the same problem with bootstrap 3 and the modal-body div's height not wanting to be greater than 442px. This was all the css needed to fix it in my case:

.modal-body {
    overflow-y: auto;
}

append multiple values for one key in a dictionary

If you want a (almost) one-liner:

from collections import deque

d = {}
deque((d.setdefault(year, []).append(value) for year, value in source_of_data), maxlen=0)

Using dict.setdefault, you can encapsulate the idea of "check if the key already exists and make a new list if not" into a single call. This allows you to write a generator expression which is consumed by deque as efficiently as possible since the queue length is set to zero. The deque will be discarded immediately and the result will be in d.

This is something I just did for fun. I don't recommend using it. There is a time and a place to consume arbitrary iterables through a deque, and this is definitely not it.

c# dictionary How to add multiple values for single key?

Here are many variations of the one answer :) My is another one and it uses extension mechanism as comfortable way to execute (handy):

public static void AddToList<T, U>(this IDictionary<T, List<U>> dict, T key, U elementToList)
{

    List<U> list;

    bool exists = dict.TryGetValue(key, out list);

    if (exists)
    {
        dict[key].Add(elementToList);
    }
    else
    {
        dict[key] = new List<U>();
        dict[key].Add(elementToList);
    }

}

Then you use it as follows:

Dictionary<int, List<string>> dict = new Dictionary<int, List<string>>();

dict.AddToList(4, "test1");
dict.AddToList(4, "test2");
dict.AddToList(4, "test3");

dict.AddToList(5, "test4");

plot with custom text for x axis points

This worked for me. Each month on X axis

str_month_list = ['January','February','March','April','May','June','July','August','September','October','November','December']
ax.set_xticks(range(0,12))
ax.set_xticklabels(str_month_list)

How to clear radio button in Javascript?

You don't need to have unique id for the elements, you can access them by their name attribute:

If you're using name="Choose", then:

With jQuery it is as simple as:

$('input[name=Choose]').attr('checked',false);

or in pure JavaScript:

   var ele = document.getElementsByName("Choose");
   for(var i=0;i<ele.length;i++)
      ele[i].checked = false;

Demo for JavaScript

How can I use modulo operator (%) in JavaScript?

It's the remainder operator and is used to get the remainder after integer division. Lots of languages have it. For example:

10 % 3 // = 1 ; because 3 * 3 gets you 9, and 10 - 9 is 1.

Apparently it is not the same as the modulo operator entirely.

Is it possible to run a .NET 4.5 app on XP?

Sadly, no, you can't run 4.5 programs on XP.

And the relevant post from that Connect page:

Posted by Microsoft on 23/03/2012 at 10:39
Thanks for the report. This behavior is by design in .NET Framework 4.5 Beta. The minimum supported operating systems are Windows 7, Windows Server 2008 SP2 and Windows Server 2008 R2 SP1. Windows XP is not a supported operating system for the Beta release.

Reorder / reset auto increment primary key

My opinion is to create a new column called row_order. then reorder that column. I'm not accepting the changes to the primary key. As an example, if the order column is banner_position, I have done something like this, This is for deleting, updating, creating of banner position column. Call this function reorder them respectively.

public function updatePositions(){
    $offers = Offer::select('banner_position')->orderBy('banner_position')->get();
    $offersCount = Offer::max('banner_position');
    $range = range(1, $offersCount);

    $existingBannerPositions = [];
    foreach($offers as $offer){
        $existingBannerPositions[] = $offer->banner_position;
    }
    sort($existingBannerPositions);
    foreach($existingBannerPositions as $key => $position){
        $numbersLessThanPosition = range(1,$position);
        $freshNumbersLessThanPosition = array_diff($numbersLessThanPosition, $existingBannerPositions);
        if(count($freshNumbersLessThanPosition)>0) {
            $existingBannerPositions[$key] = current($freshNumbersLessThanPosition);
            Offer::where('banner_position',$position)->update(array('banner_position'=> current($freshNumbersLessThanPosition)));
        }
    }
}

Taking multiple inputs from user in python

How about making the input a list. Then you may use standard list operations.

a=list(input("Enter the numbers"))

Laravel 5 not finding css files

if you are on ubuntu u can try these commands:

sudo apt install npm

npm install && npm run dev

ERROR: permission denied for sequence cities_id_seq using Postgres

Setting Spring Profile variable

For Tomcat 8:

Linux :

Create setenv.sh and update it with following:

export SPRING_PROFILES_ACTIVE=dev

Windows:

Create setenv.bat and update it with following:

set SPRING_PROFILES_ACTIVE=dev

get the margin size of an element with jquery

From jQuery's website

Shorthand CSS properties (e.g. margin, background, border) are not supported. For example, if you want to retrieve the rendered margin, use: $(elem).css('marginTop') and $(elem).css('marginRight'), and so on.

WSDL/SOAP Test With soapui

definitions is a root element of WSDL so it looks like you are not loading WSDL.

Edit:

I tested it and it looks like the whole problem is with your web server. Your web server returns WSDL to browser but it doesn't return it to any tool because these tools are using very minimalistic HTTP requests without many HTTP headers. One of missing headers is Accept. Once this header is not included in the request your server throws HTTP 400 Bad request.

The easy approach to continue is opening WSDL in the browser, save the wsdl to a file and import that file to soapUI instead of the WSDL from URL.

What is the difference between a strongly typed language and a statically typed language?

What is the difference between a strongly typed language and a statically typed language?

A statically typed language has a type system that is checked at compile time by the implementation (a compiler or interpreter). The type check rejects some programs, and programs that pass the check usually come with some guarantees; for example, the compiler guarantees not to use integer arithmetic instructions on floating-point numbers.

There is no real agreement on what "strongly typed" means, although the most widely used definition in the professional literature is that in a "strongly typed" language, it is not possible for the programmer to work around the restrictions imposed by the type system. This term is almost always used to describe statically typed languages.

Static vs dynamic

The opposite of statically typed is "dynamically typed", which means that

Values used at run time are classified into types.
There are restrictions on how such values can be used.
When those restrictions are violated, the violation is reported as a (dynamic) type error.

For example, Lua, a dynamically typed language, has a string type, a number type, and a Boolean type, among others. In Lua every value belongs to exactly one type, but this is not a requirement for all dynamically typed languages. In Lua, it is permissible to concatenate two strings, but it is not permissible to concatenate a string and a Boolean.

Strong vs weak

The opposite of "strongly typed" is "weakly typed", which means you can work around the type system. C is notoriously weakly typed because any pointer type is convertible to any other pointer type simply by casting. Pascal was intended to be strongly typed, but an oversight in the design (untagged variant records) introduced a loophole into the type system, so technically it is weakly typed. Examples of truly strongly typed languages include CLU, Standard ML, and Haskell. Standard ML has in fact undergone several revisions to remove loopholes in the type system that were discovered after the language was widely deployed.

What's really going on here?

Overall, it turns out to be not that useful to talk about "strong" and "weak". Whether a type system has a loophole is less important than the exact number and nature of the loopholes, how likely they are to come up in practice, and what are the consequences of exploiting a loophole. In practice, it's best to avoid the terms "strong" and "weak" altogether, because

Amateurs often conflate them with "static" and "dynamic".
Apparently "weak typing" is used by some persons to talk about the relative prevalance or absence of implicit conversions.
Professionals can't agree on exactly what the terms mean.
Overall you are unlikely to inform or enlighten your audience.

The sad truth is that when it comes to type systems, "strong" and "weak" don't have a universally agreed on technical meaning. If you want to discuss the relative strength of type systems, it is better to discuss exactly what guarantees are and are not provided. For example, a good question to ask is this: "is every value of a given type (or class) guaranteed to have been created by calling one of that type's constructors?" In C the answer is no. In CLU, F#, and Haskell it is yes. For C++ I am not sure—I would like to know.

By contrast, static typing means that programs are checked before being executed, and a program might be rejected before it starts. Dynamic typing means that the types of values are checked during execution, and a poorly typed operation might cause the program to halt or otherwise signal an error at run time. A primary reason for static typing is to rule out programs that might have such "dynamic type errors".

Does one imply the other?

On a pedantic level, no, because the word "strong" doesn't really mean anything. But in practice, people almost always do one of two things:

They (incorrectly) use "strong" and "weak" to mean "static" and "dynamic", in which case they (incorrectly) are using "strongly typed" and "statically typed" interchangeably.
They use "strong" and "weak" to compare properties of static type systems. It is very rare to hear someone talk about a "strong" or "weak" dynamic type system. Except for FORTH, which doesn't really have any sort of a type system, I can't think of a dynamically typed language where the type system can be subverted. Sort of by definition, those checks are bulit into the execution engine, and every operation gets checked for sanity before being executed.

Either way, if a person calls a language "strongly typed", that person is very likely to be talking about a statically typed language.

Get first day of week in SQL Server

I don't have any issues with any of the answers given here, however I do think mine is a lot simpler to implement, and understand. I have not run any performance tests on it, but it should be neglegable.

So I derived my answer from the fact that dates are stored in SQL server as integers, (I am talking about the date component only). If you don't believe me, try this SELECT CONVERT(INT, GETDATE()), and vice versa.

Now knowing this, you can do some cool math equations. You might be able to come up with a better one, but here is mine.

/*
TAKEN FROM http://msdn.microsoft.com/en-us/library/ms181598.aspx
First day of the week is
1 -- Monday
2 -- Tuesday
3 -- Wednesday
4 -- Thursday
5 -- Friday
6 -- Saturday
7 (default, U.S. English) -- Sunday
*/

--Offset is required to compensate for the fact that my @@DATEFIRST setting is 7, the default. 
DECLARE @offSet int, @testDate datetime
SELECT @offSet = 1, @testDate = GETDATE()

SELECT CONVERT(DATETIME, CONVERT(INT, @testDate) - (DATEPART(WEEKDAY, @testDate) - @offSet))

Remove a data connection from an Excel 2010 spreadsheet in compatibility mode

When the Import Data box pops up click on Properties and remove the Check Mark next to Save query definition When the Import Data box comes back and your location is where you want it to be (Ex: =$I$4) click on OK and your problem will be resolved

Javascript how to split newline

Since you are using textarea, you may find \n or \r (or \r\n) for line breaks. So, the following is suggested:

$('#keywords').val().split(/\r|\n/)

ref: check whether string contains a line break

inherit from two classes in C#

Make two interfaces IA and IB:

public interface IA
{
    public void methodA(int value);
}

public interface IB
{
    public void methodB(int value);
}

Next make A implement IA and B implement IB.

public class A : IA
{
    public int fooA { get; set; }
    public void methodA(int value) { fooA = value; }
}

public class B : IB
{
    public int fooB { get; set; }
    public void methodB(int value) { fooB = value; }
}

Then implement your C class as follows:

public class C : IA, IB
{
    private A _a;
    private B _b;

    public C(A _a, B _b)
    {
        this._a = _a;
        this._b = _b;
    }

    public void methodA(int value) { _a.methodA(value); }
    public void methodB(int value) { _b.methodB(value); }
}

Generally this is a poor design overall because you can have both A and B implement a method with the same name and variable types such as foo(int bar) and you will need to decide how to implement it, or if you just call foo(bar) on both _a and _b. As suggested elsewhere you should consider a .A and .B properties instead of combining the two classes.

How do you add a timer to a C# console application

You can also use your own timing mechanisms if you want a little more control, but possibly less accuracy and more code/complexity, but I would still recommend a timer. Use this though if you need to have control over the actual timing thread:

private void ThreadLoop(object callback)
{
    while(true)
    {
        ((Delegate) callback).DynamicInvoke(null);
        Thread.Sleep(5000);
    }
}

would be your timing thread(modify this to stop when reqiuired, and at whatever time interval you want).

and to use/start you can do:

Thread t = new Thread(new ParameterizedThreadStart(ThreadLoop));

t.Start((Action)CallBack);

Callback is your void parameterless method that you want called at each interval. For example:

private void CallBack()
{
    //Do Something.
}

How do I check if a variable exists?

Like so:

def no(var):
    "give var as a string (quote it like 'var')"
    assert(var not in vars())
    assert(var not in globals())
    assert(var not in vars(__builtins__))
    import keyword
    assert(var not in keyword.kwlist)

Then later:

no('foo')
foo = ....

If your new variable foo is not safe to use, you'll get an AssertionError exception which will point to the line that failed, and then you will know better. Here is the obvious contrived self-reference:

no('no')

---------------------------------------------------------------------------
AssertionError                            Traceback (most recent call last)
<ipython-input-88-d14ecc6b025a> in <module>
----> 1 no('no')

<ipython-input-86-888a9df72be0> in no(var)
      2     "give var as a string (quote it)"
      3     assert( var not in vars())
----> 4     assert( var not in globals())
      5     assert( var not in vars(__builtins__))
      6     import keyword

AssertionError:

Sharing link on WhatsApp from mobile website (not application) for Android

Try to make it this way:

<a href="https://wa.me/(phone)?text=(text URL encoded)">Link</a>

Even you can send messages without enter the phone number in the link:

<a href="https://wa.me/?text=Hello%20world!">Say hello</a>

After clicking on the link, you will be shown a list of contacts you can send your message to.

More info in https://faq.whatsapp.com/en/general/26000030.

Good luck!

How to put a text beside the image?

make the image float: left; and the text float: right;

Take a look at this fiddle I used a picture online but you can just swap it out for your picture.

Where does PHP's error log reside in XAMPP?

You can also open the xampp control panel and click on the Button "logs":

You are trying to add a non-nullable field 'new_field' to userprofile without a default

If "website" can be empty than new_field should also be set to be empty.

Now if you want to add logic on save where if new_field is empty to grab the value from "website" all you need to do is override the save function for your Model like this:

class UserProfile(models.Model):
    user = models.OneToOneField(User)
    website = models.URLField(blank=True, default='DEFAULT VALUE')
    new_field = models.CharField(max_length=140, blank=True, default='DEFAULT VALUE')

    def save(self, *args, **kwargs):
        if not self.new_field:
            # Setting the value of new_field with website's value
            self.new_field = self.website

        # Saving the object with the default save() function
        super(UserProfile, self).save(*args, **kwargs)

Python UTC datetime object's ISO format doesn't include Z (Zulu or Zero offset)

In Python >= 3.2 you can simply use this:

>>> from datetime import datetime, timezone
>>> datetime.now(timezone.utc).isoformat()
'2019-03-14T07:55:36.979511+00:00'

Int to Decimal Conversion - Insert decimal point at specified location

Simple math.

double result = ((double)number) / 100.0;

Although you may want to use decimal rather than double: decimal vs double! - Which one should I use and when?

Validate that end date is greater than start date with jQuery

Reference jquery.validate.js and jquery-1.2.6.js. Add a startDate class to your start date textbox. Add an endDate class to your end date textbox.

Add this script block to your page:-

<script type="text/javascript">
    $(document).ready(function() {
        $.validator.addMethod("endDate", function(value, element) {
            var startDate = $('.startDate').val();
            return Date.parse(startDate) <= Date.parse(value) || value == "";
        }, "* End date must be after start date");
        $('#formId').validate();
    });
</script>

Hope this helps :-)

How to find sum of multiple columns in a table in SQL Server 2005?

Another example using COALESCE. http://sqlmag.com/t-sql/coalesce-vs-isnull

SELECT (COALESCE(SUM(val1),0) + COALESCE(SUM(val2), 0)
+ COALESCE(SUM(val3), 0) + COALESCE(SUM(val4), 0)) AS 'TOTAL'
FROM Emp

Babel 6 regeneratorRuntime is not defined

for future reference :

As of Babel version 7.0.0-beta.55 stage presets have been removed

refer blog https://babeljs.io/blog/2018/07/27/removing-babels-stage-presets

async await can be still be used by

https://babeljs.io/docs/en/babel-plugin-transform-async-to-generator#usage

installation

npm install --save-dev @babel/plugin-transform-async-to-generator

usage in .babelrc

 { 
     "presets": ["@babel/preset-env"],
     "plugins": ["@babel/plugin-transform-async-to-generator"]
 }

and using babel polyfill https://babeljs.io/docs/en/babel-polyfill

installation

npm install --save @babel/polyfill

webpack.config.js

module.exports = {
  entry: ["@babel/polyfill", "./app/js"],
};

Portable way to check if directory exists [Windows/Linux, C]

You can use the GTK glib to abstract from OS stuff.

glib provides a g_dir_open() function which should do the trick.

Java: JSON -> Protobuf & back conversion

Well, there is no shortcut to do it as per my findings, but somehow you
an achieve it in few simple steps

First you have to declare a bean of type 'ProtobufJsonFormatHttpMessageConverter'

@Bean  
@Primary  
public ProtobufJsonFormatHttpMessageConverter protobufHttpMessageConverter() {  
  return new ProtobufJsonFormatHttpMessageConverter(JsonFormat.parser(), JsonFormat.printer());  
}

Then you can just write an Utility class like ResponseBuilder, because it can parse the request by default but without these changes it can not produce Json response. and then you can write few methods to convert the response types to its related object type.

public static <T> T build(Message message, Class<T> type) {
  Printer printer = JsonFormat.printer();
  Gson gson = new Gson();
  try {
    return gson.fromJson(printer.print(message), type);
  } catch (JsonSyntaxException | InvalidProtocolBufferException e) {
    throw new ApiException(HttpStatus.INTERNAL_SERVER_ERROR, "Response   conversion Error", e);
  }
}

Then you can call this method from your controller class as last line like -

return ResponseBuilder.build(<returned_service_object>, <Type>);

Hope this will help you to implement protobuf in json format.

How to grep a string in a directory and all its subdirectories?

grep -r -e string directory

-r is for recursive; -e is optional but its argument specifies the regex to search for. Interestingly, POSIX grep is not required to support -r (or -R), but ~~I'm practically certain that System V grep did, so~~ in practice they (almost) all do. Some versions of grep support -R as well as (or conceivably instead of) -r; AFAICT, it means the same thing.

How to create a Rectangle object in Java using g.fillRect method

Note:drawRect and fillRect are different.

Draws the outline of the specified rectangle:

public void drawRect(int x,
        int y,
        int width,
        int height)

Fills the specified rectangle. The rectangle is filled using the graphics context's current color:

public abstract void fillRect(int x,
        int y,
        int width,
        int height)

PyCharm import external library

In my case, the correct menu path was:

File > Default settings > Project Interpreter

How to tell which commit a tag points to in Git?

From git mailing list, here is the way to get the list of commit hashes for tags with automatic dereferencing for annotated tags:

git for-each-ref --format='%(if)%(*objectname)%(then)%(*objectname)%(else)%(objectname)%(end) %(refname)' refs/tags

Converting a char to uppercase

You can apply the .toUpperCase() directly on String variables or as an attribute to text fields. Ex: -

String str;
TextView txt;

str.toUpperCase();// will change it to all upper case OR
txt.append(str.toUpperCase());
txt.setText(str.toUpperCase());

How do I compile C++ with Clang?

The command clang is for C, and the command clang++ is for C++.

How to check if dropdown is disabled?

There are two options:

First

You can also use like is()

$('#dropDownId').is(':disabled');

Second

Using == true by checking if the attributes value is disabled. attr()

$('#dropDownId').attr('disabled');

whatever you feel fits better , you can use :)

Cheers!

Trigger Change event when the Input value changed programmatically?

If someone is using react, following will be useful:

https://stackoverflow.com/a/62111884/1015678

const valueSetter = Object.getOwnPropertyDescriptor(this.textInputRef, 'value').set;
const prototype = Object.getPrototypeOf(this.textInputRef);
const prototypeValueSetter = Object.getOwnPropertyDescriptor(prototype, 'value').set;
if (valueSetter && valueSetter !== prototypeValueSetter) {
    prototypeValueSetter.call(this.textInputRef, 'new value');
} else {
    valueSetter.call(this.textInputRef, 'new value');
}
this.textInputRef.dispatchEvent(new Event('input', { bubbles: true }));

How to clear an EditText on click?

I'm not sure if you are after this, but try this XML:

android:hint="Enter Name"

It displays that text when the input field is empty, selected or unselected.

Or if you want it to do exactly as you described, assign a onClickListener on the editText and set it empty with setText().

Send a ping to each IP on a subnet

for i in $(seq 1 254); do ping -c1 -t 1 192.168.11.$i; done

Adding a -t 1 waits only one second before exiting. This improves the speed a lot if you just have a few devices connected to that subnet.

Undefined reference to pow( ) in C, despite including math.h

You need to link with the math library:

gcc -o sphere sphere.c -lm

The error you are seeing: error: ld returned 1 exit status is from the linker ld (part of gcc that combines the object files) because it is unable to find where the function pow is defined.

Including math.h brings in the declaration of the various functions and not their definition. The def is present in the math library libm.a. You need to link your program with this library so that the calls to functions like pow() are resolved.

Get the latest record from mongodb collection

If you are using auto-generated Mongo Object Ids in your document, it contains timestamp in it as first 4 bytes using which latest doc inserted into the collection could be found out. I understand this is an old question, but if someone is still ending up here looking for one more alternative.

db.collectionName.aggregate(
[{$group: {_id: null, latestDocId: { $max: "$_id"}}}, {$project: {_id: 0, latestDocId: 1}}])

Above query would give the _id for the latest doc inserted into the collection

Pandas index column title or name

df.columns.values also give us the column names

How to set corner radius of imageView?

You can define border radius of any view providing an "User defined Runtime Attributes", providing key path "layer.cornerRadius" of type string and then the value of radius you need ;) See attached images below:

Configuring in XCode

Groovy method with optional parameters

Can't be done as it stands... The code

def myMethod(pParm1='1', pParm2='2'){
    println "${pParm1}${pParm2}"
}

Basically makes groovy create the following methods:

Object myMethod( pParm1, pParm2 ) {
    println "$pParm1$pParm2"
}

Object myMethod( pParm1 ) {
    this.myMethod( pParm1, '2' )
}

Object myMethod() {
    this.myMethod( '1', '2' )
}

One alternative would be to have an optional Map as the first param:

def myMethod( Map map = [:], String mandatory1, String mandatory2 ){
    println "${mandatory1} ${mandatory2} ${map.parm1 ?: '1'} ${map.parm2 ?: '2'}"
}

myMethod( 'a', 'b' )                // prints 'a b 1 2'
myMethod( 'a', 'b', parm1:'value' ) // prints 'a b value 2'
myMethod( 'a', 'b', parm2:'2nd')    // prints 'a b 1 2nd'

Obviously, documenting this so other people know what goes in the magical map and what the defaults are is left to the reader ;-)

How do I get first element rather than using [0] in jQuery?

You can use the first method:

$('li').first()

http://api.jquery.com/first/

btw I agree with Nick Craver -- use document.getElementById()...

OSX - How to auto Close Terminal window after the "exit" command executed.

Create a script:

cat ~/exit.scpt

like this:

Note: If there is only one window, just quit the application, else simulate command + w to close the tab)

tell application "Terminal" set WindowNum to get window count if WindowNum = 1 then quit else tell application "System Events" to keystroke "w" using command down end if end tell

Then add a alias in your *shrc

just like vi ~/.bashrc or zshrc (anything else?)

add it: alias exit="osascript ~/exit.scpt"

And source the ~/.bashrc or reopen your terminal.app

Query to get the names of all tables in SQL Server 2008 Database

sys.tables

Contains all tables. so exec this query to get all tables with details.

SELECT * FROM sys.tables

or simply select Name from sys.tables to get the name of all tables.

SELECT Name From sys.tables

Java unsupported major minor version 52.0

Your code was compiled with Java Version 1.8 while it is being executed with Java Version 1.7 or below.

In your case it seems that two different Java installations are used, the newer to compile and the older to execute your code.

Try recompiling your code with Java 1.7 or upgrade your Java Plugin.

How long will my session last?

You're searching for gc_maxlifetime, see http://php.net/manual/en/session.configuration.php#ini.session.gc-maxlifetime for a description.

Your session will last 1440 seconds which is 24 minutes (default).

How do you debug MySQL stored procedures?

Yes, there is a specialized tools for this kind of thing - MySQL Debugger.
enter image description here

How do I trim whitespace?

This will remove all whitespace and newlines from both the beginning and end of a string:

>>> s = "  \n\t  \n   some \n text \n     "
>>> re.sub("^\s+|\s+$", "", s)
>>> "some \n text"

Send Email Intent

Use this:

boolean success = EmailIntentBuilder.from(activity)
        .to("[email protected]")
        .cc("[email protected]")
        .subject("Error report")
        .body(buildErrorReport())
        .start();

use build gradle :

compile 'de.cketti.mailto:email-intent-builder:1.0.0'

Change Spinner dropdown icon

For this you can use .9 Patch Image and just simply set it in to background.

android:background="@drawable/spin"

Here i'll give you .9patch image. try with this.

Right click on image and click Save Image as

set image name like this : anyname.9.png and hit save.

Enjoy.. Happy Coading. :)

Should I use the Reply-To header when sending emails as a service to others?

I tested dkarp's solution with gmail and it was filtered to spam. Use the Reply-To header instead (or in addition, although gmail apparently doesn't need it). Here's how linkedin does it:

Sender: [email protected]
From: John Doe via LinkedIn <[email protected]>
Reply-To: John Doe <[email protected]>
To: My Name <[email protected]>

Once I switched to this format, gmail is no longer filtering my messages as spam.

Set language for syntax highlighting in Visual Studio Code

Press Ctrl + KM and then type in (or click) the language you want.

Alternatively, to access it from the command palette, look for "Change Language Mode" as seen below:

jQuery - Trigger event when an element is removed from the DOM

You can use jQuery special events for this.

In all simplicity,

Setup:

(function($){
  $.event.special.destroyed = {
    remove: function(o) {
      if (o.handler) {
        o.handler()
      }
    }
  }
})(jQuery)

Usage:

$('.thing').bind('destroyed', function() {
  // do stuff
})

Addendum to answer Pierre and DesignerGuy's comments:

To not have the callback fire when calling $('.thing').off('destroyed'), change the if condition to: if (o.handler && o.type !== 'destroyed') { ... }

Resource interpreted as stylesheet but transferred with MIME type text/html (seems not related with web server)

I was facing similar issue. And Exploring solutions in this fantastic Stack Overflow page.

user54861 's response (mismatching names in case sensetivity) makes me curious to inspect my code again and realized that "I didnt upload two js files that I loaded them in head tag". :-)

When I uploaded them the issue runs away ! And code runs and page rendered without any another error!

So, moral of the story is don't forget to make sure that all of your js files are uploaded where the page is looking for them.

How do I pass environment variables to Docker containers?

Use -e or --env value to set environment variables (default []).

An example from a startup script:

 docker run  -e myhost='localhost' -it busybox sh

If you want to use multiple environments from the command line then before every environment variable use the -e flag.

Example:

 sudo docker run -d -t -i -e NAMESPACE='staging' -e PASSWORD='foo' busybox sh

Note: Make sure put the container name after the environment variable, not before that.

If you need to set up many variables, use the --env-file flag

For example,

 $ docker run --env-file ./my_env ubuntu bash

For any other help, look into the Docker help:

 $ docker run --help

Official documentation: https://docs.docker.com/compose/environment-variables/

Convert International String to \u Codes in java

Here's an improved version of ArtB's answer:

    StringBuilder b = new StringBuilder();

    for (char c : input.toCharArray()) {
        if (c >= 128)
            b.append("\\u").append(String.format("%04X", (int) c));
        else
            b.append(c);
    }

    return b.toString();

This version escapes all non-ASCII chars and works correctly for low Unicode code points like Ä.

Format certain floating dataframe columns into percentage in pandas

You could also set the default format for float :

pd.options.display.float_format = '{:.2%}'.format

Use '{:.2%}' instead of '{:.2f}%' - The former converts 0.41 to 41.00% (correctly), the latter to 0.41% (incorrectly)

href around input type submit

Why would you want to put a submit button inside an anchor? You are either trying to submit a form or go to a different page. Which one is it?

Either submit the form:

<input type="submit" class="button_active" value="1" />

Or go to another page:

<input type="button" class="button_active" onclick="location.href='1.html';" />

How do I pass parameters to a jar file at the time of execution?

java [ options ] -jar file.jar [ argument ... ]

if you need to pass the log4j properties file use the below option

-Dlog4j.configurationFile=directory/file.xml


java -Dlog4j.configurationFile=directory/file.xml -jar <JAR FILE> [arguments ...]

How to use switch statement inside a React component?

You can't have a switch in render. The psuedo-switch approach of placing an object-literal that accesses one element isn't ideal because it causes all views to process and that can result in dependency errors of props that don't exist in that state.

Here's a nice clean way to do it that doesn't require each view to render in advance:

render () {
  const viewState = this.getViewState();

  return (
    <div>
      {viewState === ViewState.NO_RESULTS && this.renderNoResults()}
      {viewState === ViewState.LIST_RESULTS && this.renderResults()}
      {viewState === ViewState.SUCCESS_DONE && this.renderCompleted()}
    </div>
  )

If your conditions for which view state are based on more than a simple property – like multiple conditions per line, then an enum and a getViewState function to encapsulate the conditions is a nice way to separate this conditional logic and cleanup your render.

Is there a limit on how much JSON can hold?

JSON is similar to other data formats like XML - if you need to transmit more data, you just send more data. There's no inherent size limitation to the JSON request. Any limitation would be set by the server parsing the request. (For instance, ASP.NET has the "MaxJsonLength" property of the serializer.)

pass kwargs argument to another function with kwargs

For #2 args will be only a formal parameter with dict value, but not a keyword type parameter.

If you want to pass a keyword type parameter into a keyword argument You need to specific ** before your dictionary, which means **args

check this out for more detail on using **kw

http://www.saltycrane.com/blog/2008/01/how-to-use-args-and-kwargs-in-python/

Test only if variable is not null in if statement

I don't believe the expression is sensical as it is.

Elvis means "if truthy, use the value, else use this other thing."

Your "other thing" is a closure, and the value is status != null, neither of which would seem to be what you want. If status is null, Elvis says true. If it's not, you get an extra layer of closure.

Why can't you just use:

(it.description == desc) && ((status == null) || (it.status == status))

Even if that didn't work, all you need is the closure to return the appropriate value, right? There's no need to create two separate find calls, just use an intermediate variable.

What is the default stack size, can it grow, how does it work with garbage collection?

As you say, local variables and references are stored on the stack. When a method returns, the stack pointer is simply moved back to where it was before the method started, that is, all local data is "removed from the stack". Therefore, there is no garbage collection needed on the stack, that only happens in the heap.

To answer your specific questions:

See this question on how to increase the stack size.
You can limit the stack growth by:
- grouping many local variables in an object: that object will be stored in the heap and only the reference is stored on the stack
- limit the number of nested function calls (typically by not using recursion)
For windows, the default stack size is 320k for 32bit and 1024k for 64bit, see this link.

How do I iterate through each element in an n-dimensional matrix in MATLAB?

You could make a recursive function do the work

Let L = size(M)
Let idx = zeros(L,1)
Take length(L) as the maximum depth
Loop for idx(depth) = 1:L(depth)
If your depth is length(L), do the element operation, else call the function again with depth+1

Not as fast as vectorized methods if you want to check all the points, but if you don't need to evaluate most of them it can be quite a time saver.

How can I search an array in VB.NET?

Dim arr() As String = {"ravi", "Kumar", "Ravi", "Ramesh"}
Dim result = arr.Where(Function(a) a.Contains("ra")).Select(Function(s) Array.IndexOf(arr, s)).ToArray()

string[] arr = { "ravi", "Kumar", "Ravi", "Ramesh" };
var result = arr.Where(a => a.Contains("Ra")).Select(a => Array.IndexOf(arr, a)).ToArray();

-----Detailed------

Module Module1

    Sub Main()
        Dim arr() As String = {"ravi", "Kumar", "Ravi", "Ramesh"}
        Dim searchStr = "ra"
        'Not case sensitive - checks if item starts with searchStr
        Dim result1 = arr.Where(Function(a) a.ToLower.StartsWith(searchStr)).Select(Function(s) Array.IndexOf(arr, s)).ToArray
        'Case sensitive - checks if item starts with searchStr
        Dim result2 = arr.Where(Function(a) a.StartsWith(searchStr)).Select(Function(s) Array.IndexOf(arr, s)).ToArray
        'Not case sensitive - checks if item contains searchStr
        Dim result3 = arr.Where(Function(a) a.ToLower.Contains(searchStr)).Select(Function(s) Array.IndexOf(arr, s)).ToArray
        Stop
    End Sub

End Module

How to split one string into multiple strings separated by at least one space in bash shell?

Probably the easiest and most secure way in BASH 3 and above is:

var="string    to  split"
read -ra arr <<<"$var"

(where arr is the array which takes the split parts of the string) or, if there might be newlines in the input and you want more than just the first line:

var="string    to  split"
read -ra arr -d '' <<<"$var"

(please note the space in -d ''; it cannot be omitted), but this might give you an unexpected newline from <<<"$var" (as this implicitly adds an LF at the end).

Example:

touch NOPE
var="* a  *"
read -ra arr <<<"$var"
for a in "${arr[@]}"; do echo "[$a]"; done

Outputs the expected

[*]
[a]
[*]

as this solution (in contrast to all previous solutions here) is not prone to unexpected and often uncontrollable shell globbing.

Also this gives you the full power of IFS as you probably want:

Example:

IFS=: read -ra arr < <(grep "^$USER:" /etc/passwd)
for a in "${arr[@]}"; do echo "[$a]"; done

Outputs something like:

[tino]
[x]
[1000]
[1000]
[Valentin Hilbig]
[/home/tino]
[/bin/bash]

As you can see, spaces can be preserved this way, too:

IFS=: read -ra arr <<<' split  :   this    '
for a in "${arr[@]}"; do echo "[$a]"; done

outputs

[ split  ]
[   this    ]

Please note that the handling of IFS in BASH is a subject on its own, so do your tests; some interesting topics on this:

unset IFS: Ignores runs of SPC, TAB, NL and on line starts and ends
IFS='': No field separation, just reads everything
IFS=' ': Runs of SPC (and SPC only)

Some last examples:

var=$'\n\nthis is\n\n\na test\n\n'
IFS=$'\n' read -ra arr -d '' <<<"$var"
i=0; for a in "${arr[@]}"; do let i++; echo "$i [$a]"; done

outputs

1 [this is]
2 [a test]

while

unset IFS
var=$'\n\nthis is\n\n\na test\n\n'
read -ra arr -d '' <<<"$var"
i=0; for a in "${arr[@]}"; do let i++; echo "$i [$a]"; done

outputs

1 [this]
2 [is]
3 [a]
4 [test]

BTW:

If you are not used to $'ANSI-ESCAPED-STRING' get used to it; it's a timesaver.
If you do not include -r (like in read -a arr <<<"$var") then read does backslash escapes. This is left as exercise for the reader.

For the second question:

To test for something in a string I usually stick to case, as this can check for multiple cases at once (note: case only executes the first match, if you need fallthrough use multiple case statements), and this need is quite often the case (pun intended):

case "$var" in
'')                empty_var;;                # variable is empty
*' '*)             have_space "$var";;        # have SPC
*[[:space:]]*)     have_whitespace "$var";;   # have whitespaces like TAB
*[^-+.,A-Za-z0-9]*) have_nonalnum "$var";;    # non-alphanum-chars found
*[-+.,]*)          have_punctuation "$var";;  # some punctuation chars found
*)                 default_case "$var";;      # if all above does not match
esac

So you can set the return value to check for SPC like this:

case "$var" in (*' '*) true;; (*) false;; esac

Why case? Because it usually is a bit more readable than regex sequences, and thanks to Shell metacharacters it handles 99% of all needs very well.

UIButton Image + Text IOS

Xcode-9 and Xcode-10 Apple done few changes regarding Edge Inset now, you can change it under size-inspector.

Please follow below steps:

Step-1: Input text and select image which you want to show:

Step-2: Select button control as per your requirement as shown in below image:

Step-3: Now go-to size inspector and add value as per your requirement:

How is a tag different from a branch in Git? Which should I use, here?

A tag represents a version of a particular branch at a moment in time. A branch represents a separate thread of development that may run concurrently with other development efforts on the same code base. Changes to a branch may eventually be merged back into another branch to unify them.

Usually you'll tag a particular version so that you can recreate it, e.g., this is the version we shipped to XYZ Corp. A branch is more of a strategy to provide on-going updates on a particular version of the code while continuing to do development on it. You'll make a branch of the delivered version, continue development on the main line, but make bug fixes to the branch that represents the delivered version. Eventually, you'll merge these bug fixes back into the main line. Often you'll use both branching and tagging together. You'll have various tags that may apply both to the main line and its branches marking particular versions (those delivered to customers, for instance) along each branch that you may want to recreate -- for delivery, bug diagnosis, etc.

It's actually more complicated than this -- or as complicated as you want to make it -- but these examples should give you an idea of the differences.

How to get current memory usage in android?

CAUTION: This answer measures memory usage/available of the DEVICE. This is NOT what is available to your app. To measure what your APP is doing, and is PERMITTED to do, Use android developer's answer.

Android docs - ActivityManager.MemoryInfo

parse /proc/meminfo command. You can find reference code here: Get Memory Usage in Android

use below code and get current RAM:

MemoryInfo mi = new MemoryInfo();
ActivityManager activityManager = (ActivityManager) getSystemService(ACTIVITY_SERVICE);
activityManager.getMemoryInfo(mi);
double availableMegs = mi.availMem / 0x100000L;

//Percentage can be calculated for API 16+
double percentAvail = mi.availMem / (double)mi.totalMem * 100.0;

Explanation of the number 0x100000L

1024 bytes      == 1 Kibibyte 
1024 Kibibyte   == 1 Mebibyte

1024 * 1024     == 1048576
1048576         == 0x100000

It's quite obvious that the number is used to convert from bytes to mebibyte

P.S: we need to calculate total memory only once. so call point 1 only once in your code and then after, you can call code of point 2 repetitively.

SSLHandshakeException: No subject alternative names present

Thanks,Bruno for giving me heads up on Common Name and Subject Alternative Name. As we figured out certificate was generated with CN with DNS name of network and asked for regeneration of new certificate with Subject Alternative Name entry i.e. san=ip:10.0.0.1. which is the actual solution.

But, we managed to find out a workaround with which we can able to run on development phase. Just add a static block in the class from which we are making ssl connection.

static {
    HttpsURLConnection.setDefaultHostnameVerifier(new HostnameVerifier()
        {
            public boolean verify(String hostname, SSLSession session)
            {
                // ip address of the service URL(like.23.28.244.244)
                if (hostname.equals("23.28.244.244"))
                    return true;
                return false;
            }
        });
}

If you happen to be using Java 8, there is a much slicker way of achieving the same result:

static {
    HttpsURLConnection.setDefaultHostnameVerifier((hostname, session) -> hostname.equals("127.0.0.1"));
}

How to pass an array into a SQL Server stored procedure

I've been searching through all the examples and answers of how to pass any array to sql server without the hassle of creating new Table type,till i found this linK, below is how I applied it to my project:

--The following code is going to get an Array as Parameter and insert the values of that --array into another table

Create Procedure Proc1 


@UserId int, //just an Id param
@s nvarchar(max)  //this is the array your going to pass from C# code to your Sproc

AS

    declare @xml xml

    set @xml = N'<root><r>' + replace(@s,',','</r><r>') + '</r></root>'

    Insert into UserRole (UserID,RoleID)
    select 
       @UserId [UserId], t.value('.','varchar(max)') as [RoleId]


    from @xml.nodes('//root/r') as a(t)
END

Hope you enjoy it

How can I delete a newline if it is the last character in a file?

You can do this with head from GNU coreutils, it supports arguments that are relative to the end of the file. So to leave off the last byte use:

head -c -1

To test for an ending newline you can use tail and wc. The following example saves the result to a temporary file and subsequently overwrites the original:

if [[ $(tail -c1 file | wc -l) == 1 ]]; then
  head -c -1 file > file.tmp
  mv file.tmp file
fi

You could also use sponge from moreutils to do "in-place" editing:

[[ $(tail -c1 file | wc -l) == 1 ]] && head -c -1 file | sponge file

You can also make a general reusable function by stuffing this in your .bashrc file:

# Example:  remove-last-newline < multiline.txt
function remove-last-newline(){
    local file=$(mktemp)
    cat > $file
    if [[ $(tail -c1 $file | wc -l) == 1 ]]; then
        head -c -1 $file > $file.tmp
        mv $file.tmp $file
    fi
    cat $file
}

Update

As noted by KarlWilbur in the comments and used in Sorentar's answer, truncate --size=-1 can replace head -c-1 and supports in-place editing.

How to set the holo dark theme in a Android app?

change parent="android:Theme.Holo.Dark" to parent="android:Theme.Holo"

The holo dark theme is called Holo

How to return JSON data from spring Controller using @ResponseBody

When I was facing this issue, I simply put just getter setter methods and my issues were resolved.

I am using Spring boot version 2.0.

How do I disable a Pylint warning?

In case this helps someone, if you're using Visual Studio Code, it expects the file to be in UTF-8 encoding. To generate the file, I ran pylint --generate-rcfile | out-file -encoding utf8 .pylintrc in PowerShell.

ubuntu "No space left on device" but there is tons of space

It's possible that you've run out of memory or some space elsewhere and it prompted the system to mount an overflow filesystem, and for whatever reason, it's not going away.

Try unmounting the overflow partition:

umount /tmp

umount overflow

Rails ActiveRecord date between

I have been using the 3 dots, instead of 2. Three dots gives you a range that is open at the beginning and closed at the end, so if you do 2 queries for subsequent ranges, you can't get the same row back in both.

2.2.2 :003 > Comment.where(updated_at: 2.days.ago.beginning_of_day..1.day.ago.beginning_of_day)
Comment Load (0.3ms)  SELECT "comments".* FROM "comments" WHERE ("comments"."updated_at" BETWEEN '2015-07-12 00:00:00.000000' AND '2015-07-13 00:00:00.000000')
=> #<ActiveRecord::Relation []> 
2.2.2 :004 > Comment.where(updated_at: 2.days.ago.beginning_of_day...1.day.ago.beginning_of_day)
Comment Load (0.3ms)  SELECT "comments".* FROM "comments" WHERE ("comments"."updated_at" >= '2015-07-12 00:00:00.000000' AND "comments"."updated_at" < '2015-07-13 00:00:00.000000')
=> #<ActiveRecord::Relation []>

And, yes, always nice to use a scope!

Get div tag scroll position using JavaScript

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
    <script type="text/javascript">
        function scollPos() {
            var div = document.getElementById("myDiv").scrollTop;
            document.getElementById("pos").innerHTML = div;
        }
    </script>
</head>
<body>
    <form id="form1">
    <div id="pos">
    </div>
    <div id="myDiv" style="overflow: auto; height: 200px; width: 200px;" onscroll="scollPos();">
        Place some large content here
    </div>
    </form>
</body>
</html>

JSTL if tag for equal strings

You can use scriptlets, however, this is not the way to go. Nowdays inline scriplets or JAVA code in your JSP files is considered a bad habit.

You should read up on JSTL a bit more. If the ansokanInfo object is in your request or session scope, printing the object (toString() method) like this: ${ansokanInfo} can give you some base information. ${ansokanInfo.pSystem} should call the object getter method. If this all works, you can use this:

<c:if test="${ ansokanInfo.pSystem  == 'NAT'}"> tataa </c:if>

Query to list number of records in each table in a database

From this question: https://dba.stackexchange.com/questions/114958/list-all-tables-from-all-user-databases/230411#230411

I added record count to the answer provided by @Aaron Bertrand that lists all databases and all tables.

DECLARE @src NVARCHAR(MAX), @sql NVARCHAR(MAX);

SELECT @sql = N'', @src = N' UNION ALL 
SELECT ''$d'' as ''database'', 
    s.name COLLATE SQL_Latin1_General_CP1_CI_AI as ''schema'',
    t.name COLLATE SQL_Latin1_General_CP1_CI_AI as ''table'' ,
    ind.rows as record_count
  FROM [$d].sys.schemas AS s
  INNER JOIN [$d].sys.tables AS t ON s.[schema_id] = t.[schema_id]
  INNER JOIN [$d].sys.sysindexes AS ind ON t.[object_id] = ind.[id]
  where ind.indid < 2';

SELECT @sql = @sql + REPLACE(@src, '$d', name)
  FROM sys.databases
  WHERE database_id > 4
    AND [state] = 0
    AND HAS_DBACCESS(name) = 1;

SET @sql = STUFF(@sql, 1, 10, CHAR(13) + CHAR(10));

PRINT @sql;
--EXEC sys.sp_executesql @sql;

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